'use strict';
/**
* @license Angular v19.2.13
* (c) 2010-2025 Google LLC. https://angular.io/
* License: MIT
*/
'use strict';
var schematics = require('@angular-devkit/schematics');
var p = require('path');
var compiler_host = require('./compiler_host-B1Gyeytz.cjs');
var checker = require('./checker-5pyJrZ9G.cjs');
var ts = require('typescript');
require('os');
require('fs');
require('module');
require('url');
function lookupIdentifiersInSourceFile(sourceFile, names) {
const results = new Set();
const visit = (node) => {
if (ts.isIdentifier(node) && names.includes(node.text)) {
results.add(node);
}
ts.forEachChild(node, visit);
};
visit(sourceFile);
return results;
}
const ngtemplate = 'ng-template';
const boundngifelse = '[ngIfElse]';
const boundngifthenelse = '[ngIfThenElse]';
const boundngifthen = '[ngIfThen]';
const nakedngfor$1 = 'ngFor';
const startMarker = '◬';
const endMarker = '✢';
const startI18nMarker = '⚈';
const endI18nMarker = '⚉';
const importRemovals = [
'NgIf',
'NgIfElse',
'NgIfThenElse',
'NgFor',
'NgForOf',
'NgForTrackBy',
'NgSwitch',
'NgSwitchCase',
'NgSwitchDefault',
];
const importWithCommonRemovals = [...importRemovals, 'CommonModule'];
function allFormsOf(selector) {
return [selector, `*${selector}`, `[${selector}]`];
}
const commonModuleDirectives = new Set([
...allFormsOf('ngComponentOutlet'),
...allFormsOf('ngTemplateOutlet'),
...allFormsOf('ngClass'),
...allFormsOf('ngPlural'),
...allFormsOf('ngPluralCase'),
...allFormsOf('ngStyle'),
...allFormsOf('ngTemplateOutlet'),
...allFormsOf('ngComponentOutlet'),
'[NgForOf]',
'[NgForTrackBy]',
'[ngIfElse]',
'[ngIfThenElse]',
]);
function pipeMatchRegExpFor(name) {
return new RegExp(`\\|\\s*${name}`);
}
const commonModulePipes = [
'date',
'async',
'currency',
'number',
'i18nPlural',
'i18nSelect',
'json',
'keyvalue',
'slice',
'lowercase',
'uppercase',
'titlecase',
'percent',
].map((name) => pipeMatchRegExpFor(name));
/**
* Represents an element with a migratable attribute
*/
class ElementToMigrate {
el;
attr;
elseAttr;
thenAttr;
forAttrs;
aliasAttrs;
nestCount = 0;
hasLineBreaks = false;
constructor(el, attr, elseAttr = undefined, thenAttr = undefined, forAttrs = undefined, aliasAttrs = undefined) {
this.el = el;
this.attr = attr;
this.elseAttr = elseAttr;
this.thenAttr = thenAttr;
this.forAttrs = forAttrs;
this.aliasAttrs = aliasAttrs;
}
normalizeConditionString(value) {
value = this.insertSemicolon(value, value.indexOf(' else '));
value = this.insertSemicolon(value, value.indexOf(' then '));
value = this.insertSemicolon(value, value.indexOf(' let '));
return value.replace(';;', ';');
}
insertSemicolon(str, ix) {
return ix > -1 ? `${str.slice(0, ix)};${str.slice(ix)}` : str;
}
getCondition() {
const chunks = this.normalizeConditionString(this.attr.value).split(';');
let condition = chunks[0];
// checks for case of no usage of `;` in if else / if then else
const elseIx = condition.indexOf(' else ');
const thenIx = condition.indexOf(' then ');
if (thenIx > -1) {
condition = condition.slice(0, thenIx);
}
else if (elseIx > -1) {
condition = condition.slice(0, elseIx);
}
let letVar = chunks.find((c) => c.search(/\s*let\s/) > -1);
return condition + (letVar ? ';' + letVar : '');
}
getTemplateName(targetStr, secondStr) {
const targetLocation = this.attr.value.indexOf(targetStr);
const secondTargetLocation = secondStr ? this.attr.value.indexOf(secondStr) : undefined;
let templateName = this.attr.value.slice(targetLocation + targetStr.length, secondTargetLocation);
if (templateName.startsWith(':')) {
templateName = templateName.slice(1).trim();
}
return templateName.split(';')[0].trim();
}
getValueEnd(offset) {
return ((this.attr.valueSpan ? this.attr.valueSpan.end.offset + 1 : this.attr.keySpan.end.offset) -
offset);
}
hasChildren() {
return this.el.children.length > 0;
}
getChildSpan(offset) {
const childStart = this.el.children[0].sourceSpan.start.offset - offset;
const childEnd = this.el.children[this.el.children.length - 1].sourceSpan.end.offset - offset;
return { childStart, childEnd };
}
shouldRemoveElseAttr() {
return ((this.el.name === 'ng-template' || this.el.name === 'ng-container') &&
this.elseAttr !== undefined);
}
getElseAttrStr() {
if (this.elseAttr !== undefined) {
const elseValStr = this.elseAttr.value !== '' ? `="${this.elseAttr.value}"` : '';
return `${this.elseAttr.name}${elseValStr}`;
}
return '';
}
start(offset) {
return this.el.sourceSpan?.start.offset - offset;
}
end(offset) {
return this.el.sourceSpan?.end.offset - offset;
}
length() {
return this.el.sourceSpan?.end.offset - this.el.sourceSpan?.start.offset;
}
}
/**
* Represents an ng-template inside a template being migrated to new control flow
*/
class Template {
el;
name;
count = 0;
contents = '';
children = '';
i18n = null;
attributes;
constructor(el, name, i18n) {
this.el = el;
this.name = name;
this.attributes = el.attrs;
this.i18n = i18n;
}
get isNgTemplateOutlet() {
return this.attributes.find((attr) => attr.name === '*ngTemplateOutlet') !== undefined;
}
get outletContext() {
const letVar = this.attributes.find((attr) => attr.name.startsWith('let-'));
return letVar ? `; context: {$implicit: ${letVar.name.split('-')[1]}}` : '';
}
generateTemplateOutlet() {
const attr = this.attributes.find((attr) => attr.name === '*ngTemplateOutlet');
const outletValue = attr?.value ?? this.name.slice(1);
return ``;
}
generateContents(tmpl) {
this.contents = tmpl.slice(this.el.sourceSpan.start.offset, this.el.sourceSpan.end.offset);
this.children = '';
if (this.el.children.length > 0) {
this.children = tmpl.slice(this.el.children[0].sourceSpan.start.offset, this.el.children[this.el.children.length - 1].sourceSpan.end.offset);
}
}
}
/** Represents a file that was analyzed by the migration. */
class AnalyzedFile {
ranges = [];
removeCommonModule = false;
canRemoveImports = false;
sourceFile;
importRanges = [];
templateRanges = [];
constructor(sourceFile) {
this.sourceFile = sourceFile;
}
/** Returns the ranges in the order in which they should be migrated. */
getSortedRanges() {
// templates first for checking on whether certain imports can be safely removed
this.templateRanges = this.ranges
.slice()
.filter((x) => x.type === 'template' || x.type === 'templateUrl')
.sort((aStart, bStart) => bStart.start - aStart.start);
this.importRanges = this.ranges
.slice()
.filter((x) => x.type === 'importDecorator' || x.type === 'importDeclaration')
.sort((aStart, bStart) => bStart.start - aStart.start);
return [...this.templateRanges, ...this.importRanges];
}
/**
* Adds a text range to an `AnalyzedFile`.
* @param path Path of the file.
* @param analyzedFiles Map keeping track of all the analyzed files.
* @param range Range to be added.
*/
static addRange(path, sourceFile, analyzedFiles, range) {
let analysis = analyzedFiles.get(path);
if (!analysis) {
analysis = new AnalyzedFile(sourceFile);
analyzedFiles.set(path, analysis);
}
const duplicate = analysis.ranges.find((current) => current.start === range.start && current.end === range.end);
if (!duplicate) {
analysis.ranges.push(range);
}
}
/**
* This verifies whether a component class is safe to remove module imports.
* It is only run on .ts files.
*/
verifyCanRemoveImports() {
const importDeclaration = this.importRanges.find((r) => r.type === 'importDeclaration');
const instances = lookupIdentifiersInSourceFile(this.sourceFile, importWithCommonRemovals);
let foundImportDeclaration = false;
let count = 0;
for (let range of this.importRanges) {
for (let instance of instances) {
if (instance.getStart() >= range.start && instance.getEnd() <= range.end) {
if (range === importDeclaration) {
foundImportDeclaration = true;
}
count++;
}
}
}
if (instances.size !== count && importDeclaration !== undefined && foundImportDeclaration) {
importDeclaration.remove = false;
}
}
}
/** Finds all non-control flow elements from common module. */
class CommonCollector extends checker.RecursiveVisitor {
count = 0;
visitElement(el) {
if (el.attrs.length > 0) {
for (const attr of el.attrs) {
if (this.hasDirectives(attr.name) || this.hasPipes(attr.value)) {
this.count++;
}
}
}
super.visitElement(el, null);
}
visitBlock(ast) {
for (const blockParam of ast.parameters) {
if (this.hasPipes(blockParam.expression)) {
this.count++;
}
}
super.visitBlock(ast, null);
}
visitText(ast) {
if (this.hasPipes(ast.value)) {
this.count++;
}
}
visitLetDeclaration(decl) {
if (this.hasPipes(decl.value)) {
this.count++;
}
super.visitLetDeclaration(decl, null);
}
hasDirectives(input) {
return commonModuleDirectives.has(input);
}
hasPipes(input) {
return commonModulePipes.some((regexp) => regexp.test(input));
}
}
/** Finds all elements that represent i18n blocks. */
class i18nCollector extends checker.RecursiveVisitor {
elements = [];
visitElement(el) {
if (el.attrs.find((a) => a.name === 'i18n') !== undefined) {
this.elements.push(el);
}
super.visitElement(el, null);
}
}
/** Finds all elements with ngif structural directives. */
class ElementCollector extends checker.RecursiveVisitor {
_attributes;
elements = [];
constructor(_attributes = []) {
super();
this._attributes = _attributes;
}
visitElement(el) {
if (el.attrs.length > 0) {
for (const attr of el.attrs) {
if (this._attributes.includes(attr.name)) {
const elseAttr = el.attrs.find((x) => x.name === boundngifelse);
const thenAttr = el.attrs.find((x) => x.name === boundngifthenelse || x.name === boundngifthen);
const forAttrs = attr.name === nakedngfor$1 ? this.getForAttrs(el) : undefined;
const aliasAttrs = this.getAliasAttrs(el);
this.elements.push(new ElementToMigrate(el, attr, elseAttr, thenAttr, forAttrs, aliasAttrs));
}
}
}
super.visitElement(el, null);
}
getForAttrs(el) {
let trackBy = '';
let forOf = '';
for (const attr of el.attrs) {
if (attr.name === '[ngForTrackBy]') {
trackBy = attr.value;
}
if (attr.name === '[ngForOf]') {
forOf = attr.value;
}
}
return { forOf, trackBy };
}
getAliasAttrs(el) {
const aliases = new Map();
let item = '';
for (const attr of el.attrs) {
if (attr.name.startsWith('let-')) {
if (attr.value === '') {
// item
item = attr.name.replace('let-', '');
}
else {
// alias
aliases.set(attr.name.replace('let-', ''), attr.value);
}
}
}
return { item, aliases };
}
}
/** Finds all elements with ngif structural directives. */
class TemplateCollector extends checker.RecursiveVisitor {
elements = [];
templates = new Map();
visitElement(el) {
if (el.name === ngtemplate) {
let i18n = null;
let templateAttr = null;
for (const attr of el.attrs) {
if (attr.name === 'i18n') {
i18n = attr;
}
if (attr.name.startsWith('#')) {
templateAttr = attr;
}
}
if (templateAttr !== null && !this.templates.has(templateAttr.name)) {
this.templates.set(templateAttr.name, new Template(el, templateAttr.name, i18n));
this.elements.push(new ElementToMigrate(el, templateAttr));
}
else if (templateAttr !== null) {
throw new Error(`A duplicate ng-template name "${templateAttr.name}" was found. ` +
`The control flow migration requires unique ng-template names within a component.`);
}
}
super.visitElement(el, null);
}
}
const startMarkerRegex = new RegExp(startMarker, 'gm');
const endMarkerRegex = new RegExp(endMarker, 'gm');
const startI18nMarkerRegex = new RegExp(startI18nMarker, 'gm');
const endI18nMarkerRegex = new RegExp(endI18nMarker, 'gm');
const replaceMarkerRegex = new RegExp(`${startMarker}|${endMarker}`, 'gm');
/**
* Analyzes a source file to find file that need to be migrated and the text ranges within them.
* @param sourceFile File to be analyzed.
* @param analyzedFiles Map in which to store the results.
*/
function analyze(sourceFile, analyzedFiles) {
forEachClass(sourceFile, (node) => {
if (ts.isClassDeclaration(node)) {
analyzeDecorators(node, sourceFile, analyzedFiles);
}
else {
analyzeImportDeclarations(node, sourceFile, analyzedFiles);
}
});
}
function checkIfShouldChange(decl, file) {
const range = file.importRanges.find((r) => r.type === 'importDeclaration');
if (range === undefined || !range.remove) {
return false;
}
// should change if you can remove the common module
// if it's not safe to remove the common module
// and that's the only thing there, we should do nothing.
const clause = decl.getChildAt(1);
return !(!file.removeCommonModule &&
clause.namedBindings &&
ts.isNamedImports(clause.namedBindings) &&
clause.namedBindings.elements.length === 1 &&
clause.namedBindings.elements[0].getText() === 'CommonModule');
}
function updateImportDeclaration(decl, removeCommonModule) {
const clause = decl.getChildAt(1);
const updatedClause = updateImportClause(clause, removeCommonModule);
if (updatedClause === null) {
return '';
}
// removeComments is set to true to prevent duplication of comments
// when the import declaration is at the top of the file, but right after a comment
// without this, the comment gets duplicated when the declaration is updated.
// the typescript AST includes that preceding comment as part of the import declaration full text.
const printer = ts.createPrinter({
removeComments: true,
});
const updated = ts.factory.updateImportDeclaration(decl, decl.modifiers, updatedClause, decl.moduleSpecifier, undefined);
return printer.printNode(ts.EmitHint.Unspecified, updated, clause.getSourceFile());
}
function updateImportClause(clause, removeCommonModule) {
if (clause.namedBindings && ts.isNamedImports(clause.namedBindings)) {
const removals = removeCommonModule ? importWithCommonRemovals : importRemovals;
const elements = clause.namedBindings.elements.filter((el) => !removals.includes(el.getText()));
if (elements.length === 0) {
return null;
}
clause = ts.factory.updateImportClause(clause, clause.isTypeOnly, clause.name, ts.factory.createNamedImports(elements));
}
return clause;
}
function updateClassImports(propAssignment, removeCommonModule) {
const printer = ts.createPrinter();
const importList = propAssignment.initializer;
// Can't change non-array literals.
if (!ts.isArrayLiteralExpression(importList)) {
return null;
}
const removals = removeCommonModule ? importWithCommonRemovals : importRemovals;
const elements = importList.elements.filter((el) => !ts.isIdentifier(el) || !removals.includes(el.text));
if (elements.length === importList.elements.length) {
// nothing changed
return null;
}
const updatedElements = ts.factory.updateArrayLiteralExpression(importList, elements);
const updatedAssignment = ts.factory.updatePropertyAssignment(propAssignment, propAssignment.name, updatedElements);
return printer.printNode(ts.EmitHint.Unspecified, updatedAssignment, updatedAssignment.getSourceFile());
}
function analyzeImportDeclarations(node, sourceFile, analyzedFiles) {
if (node.getText().indexOf('@angular/common') === -1) {
return;
}
const clause = node.getChildAt(1);
if (clause.namedBindings && ts.isNamedImports(clause.namedBindings)) {
const elements = clause.namedBindings.elements.filter((el) => importWithCommonRemovals.includes(el.getText()));
if (elements.length > 0) {
AnalyzedFile.addRange(sourceFile.fileName, sourceFile, analyzedFiles, {
start: node.getStart(),
end: node.getEnd(),
node,
type: 'importDeclaration',
remove: true,
});
}
}
}
function analyzeDecorators(node, sourceFile, analyzedFiles) {
// Note: we have a utility to resolve the Angular decorators from a class declaration already.
// We don't use it here, because it requires access to the type checker which makes it more
// time-consuming to run internally.
const decorator = ts.getDecorators(node)?.find((dec) => {
return (ts.isCallExpression(dec.expression) &&
ts.isIdentifier(dec.expression.expression) &&
dec.expression.expression.text === 'Component');
});
const metadata = decorator &&
decorator.expression.arguments.length > 0 &&
ts.isObjectLiteralExpression(decorator.expression.arguments[0])
? decorator.expression.arguments[0]
: null;
if (!metadata) {
return;
}
for (const prop of metadata.properties) {
// All the properties we care about should have static
// names and be initialized to a static string.
if (!ts.isPropertyAssignment(prop) ||
(!ts.isIdentifier(prop.name) && !ts.isStringLiteralLike(prop.name))) {
continue;
}
switch (prop.name.text) {
case 'template':
// +1/-1 to exclude the opening/closing characters from the range.
AnalyzedFile.addRange(sourceFile.fileName, sourceFile, analyzedFiles, {
start: prop.initializer.getStart() + 1,
end: prop.initializer.getEnd() - 1,
node: prop,
type: 'template',
remove: true,
});
break;
case 'imports':
AnalyzedFile.addRange(sourceFile.fileName, sourceFile, analyzedFiles, {
start: prop.name.getStart(),
end: prop.initializer.getEnd(),
node: prop,
type: 'importDecorator',
remove: true,
});
break;
case 'templateUrl':
// Leave the end as undefined which means that the range is until the end of the file.
if (ts.isStringLiteralLike(prop.initializer)) {
const path = p.join(p.dirname(sourceFile.fileName), prop.initializer.text);
AnalyzedFile.addRange(path, sourceFile, analyzedFiles, {
start: 0,
node: prop,
type: 'templateUrl',
remove: true,
});
}
break;
}
}
}
/**
* returns the level deep a migratable element is nested
*/
function getNestedCount(etm, aggregator) {
if (aggregator.length === 0) {
return 0;
}
if (etm.el.sourceSpan.start.offset < aggregator[aggregator.length - 1] &&
etm.el.sourceSpan.end.offset !== aggregator[aggregator.length - 1]) {
// element is nested
aggregator.push(etm.el.sourceSpan.end.offset);
return aggregator.length - 1;
}
else {
// not nested
aggregator.pop();
return getNestedCount(etm, aggregator);
}
}
/**
* parses the template string into the Html AST
*/
function parseTemplate(template) {
let parsed;
try {
// Note: we use the HtmlParser here, instead of the `parseTemplate` function, because the
// latter returns an Ivy AST, not an HTML AST. The HTML AST has the advantage of preserving
// interpolated text as text nodes containing a mixture of interpolation tokens and text tokens,
// rather than turning them into `BoundText` nodes like the Ivy AST does. This allows us to
// easily get the text-only ranges without having to reconstruct the original text.
parsed = new checker.HtmlParser().parse(template, '', {
// Allows for ICUs to be parsed.
tokenizeExpansionForms: true,
// Explicitly disable blocks so that their characters are treated as plain text.
tokenizeBlocks: true,
preserveLineEndings: true,
});
// Don't migrate invalid templates.
if (parsed.errors && parsed.errors.length > 0) {
const errors = parsed.errors.map((e) => ({ type: 'parse', error: e }));
return { tree: undefined, errors };
}
}
catch (e) {
return { tree: undefined, errors: [{ type: 'parse', error: e }] };
}
return { tree: parsed, errors: [] };
}
function validateMigratedTemplate(migrated, fileName) {
const parsed = parseTemplate(migrated);
let errors = [];
if (parsed.errors.length > 0) {
errors.push({
type: 'parse',
error: new Error(`The migration resulted in invalid HTML for ${fileName}. ` +
`Please check the template for valid HTML structures and run the migration again.`),
});
}
if (parsed.tree) {
const i18nError = validateI18nStructure(parsed.tree, fileName);
if (i18nError !== null) {
errors.push({ type: 'i18n', error: i18nError });
}
}
return errors;
}
function validateI18nStructure(parsed, fileName) {
const visitor = new i18nCollector();
checker.visitAll(visitor, parsed.rootNodes);
const parents = visitor.elements.filter((el) => el.children.length > 0);
for (const p of parents) {
for (const el of visitor.elements) {
if (el === p)
continue;
if (isChildOf(p, el)) {
return new Error(`i18n Nesting error: The migration would result in invalid i18n nesting for ` +
`${fileName}. Element with i18n attribute "${p.name}" would result having a child of ` +
`element with i18n attribute "${el.name}". Please fix and re-run the migration.`);
}
}
}
return null;
}
function isChildOf(parent, el) {
return (parent.sourceSpan.start.offset < el.sourceSpan.start.offset &&
parent.sourceSpan.end.offset > el.sourceSpan.end.offset);
}
/** Possible placeholders that can be generated by `getPlaceholder`. */
var PlaceholderKind;
(function (PlaceholderKind) {
PlaceholderKind[PlaceholderKind["Default"] = 0] = "Default";
PlaceholderKind[PlaceholderKind["Alternate"] = 1] = "Alternate";
})(PlaceholderKind || (PlaceholderKind = {}));
/**
* Wraps a string in a placeholder that makes it easier to identify during replacement operations.
*/
function getPlaceholder(value, kind = PlaceholderKind.Default) {
const name = `<<<ɵɵngControlFlowMigration_${kind}ɵɵ>>>`;
return `___${name}${value}${name}___`;
}
/**
* calculates the level of nesting of the items in the collector
*/
function calculateNesting(visitor, hasLineBreaks) {
// start from top of template
// loop through each element
let nestedQueue = [];
for (let i = 0; i < visitor.elements.length; i++) {
let currEl = visitor.elements[i];
if (i === 0) {
nestedQueue.push(currEl.el.sourceSpan.end.offset);
currEl.hasLineBreaks = hasLineBreaks;
continue;
}
currEl.hasLineBreaks = hasLineBreaks;
currEl.nestCount = getNestedCount(currEl, nestedQueue);
if (currEl.el.sourceSpan.end.offset !== nestedQueue[nestedQueue.length - 1]) {
nestedQueue.push(currEl.el.sourceSpan.end.offset);
}
}
}
/**
* determines if a given template string contains line breaks
*/
function hasLineBreaks(template) {
return /\r|\n/.test(template);
}
/**
* properly adjusts template offsets based on current nesting levels
*/
function reduceNestingOffset(el, nestLevel, offset, postOffsets) {
if (el.nestCount <= nestLevel) {
const count = nestLevel - el.nestCount;
// reduced nesting, add postoffset
for (let i = 0; i <= count; i++) {
offset += postOffsets.pop() ?? 0;
}
}
return offset;
}
/**
* Replaces structural directive control flow instances with block control flow equivalents.
* Returns null if the migration failed (e.g. there was a syntax error).
*/
function getTemplates(template) {
const parsed = parseTemplate(template);
if (parsed.tree !== undefined) {
const visitor = new TemplateCollector();
checker.visitAll(visitor, parsed.tree.rootNodes);
for (let [key, tmpl] of visitor.templates) {
tmpl.count = countTemplateUsage(parsed.tree.rootNodes, key);
tmpl.generateContents(template);
}
return visitor.templates;
}
return new Map();
}
function countTemplateUsage(nodes, templateName) {
let count = 0;
let isReferencedInTemplateOutlet = false;
for (const node of nodes) {
if (node.attrs) {
for (const attr of node.attrs) {
if (attr.name === '*ngTemplateOutlet' && attr.value === templateName.slice(1)) {
isReferencedInTemplateOutlet = true;
break;
}
if (attr.name.trim() === templateName) {
count++;
}
}
}
if (node.children) {
if (node.name === 'for') {
for (const child of node.children) {
if (child.value?.includes(templateName.slice(1))) {
count++;
}
}
}
count += countTemplateUsage(node.children, templateName);
}
}
return isReferencedInTemplateOutlet ? count + 2 : count;
}
function updateTemplates(template, templates) {
const updatedTemplates = getTemplates(template);
for (let [key, tmpl] of updatedTemplates) {
templates.set(key, tmpl);
}
return templates;
}
function wrapIntoI18nContainer(i18nAttr, content) {
const { start, middle, end } = generatei18nContainer(i18nAttr, content);
return `${start}${middle}${end}`;
}
function generatei18nContainer(i18nAttr, middle) {
const i18n = i18nAttr.value === '' ? 'i18n' : `i18n="${i18nAttr.value}"`;
return { start: ``, middle, end: `` };
}
/**
* Counts, replaces, and removes any necessary ng-templates post control flow migration
*/
function processNgTemplates(template, sourceFile) {
// count usage
try {
const templates = getTemplates(template);
// swap placeholders and remove
for (const [name, t] of templates) {
const replaceRegex = new RegExp(getPlaceholder(name.slice(1)), 'g');
const forRegex = new RegExp(getPlaceholder(name.slice(1), PlaceholderKind.Alternate), 'g');
const forMatches = [...template.matchAll(forRegex)];
const matches = [...forMatches, ...template.matchAll(replaceRegex)];
let safeToRemove = true;
if (matches.length > 0) {
if (t.i18n !== null) {
const container = wrapIntoI18nContainer(t.i18n, t.children);
template = template.replace(replaceRegex, container);
}
else if (t.children.trim() === '' && t.isNgTemplateOutlet) {
template = template.replace(replaceRegex, t.generateTemplateOutlet());
}
else if (forMatches.length > 0) {
if (t.count === 2) {
template = template.replace(forRegex, t.children);
}
else {
template = template.replace(forRegex, t.generateTemplateOutlet());
safeToRemove = false;
}
}
else {
template = template.replace(replaceRegex, t.children);
}
const dist = matches.filter((obj, index, self) => index === self.findIndex((t) => t.input === obj.input));
if ((t.count === dist.length || t.count - matches.length === 1) && safeToRemove) {
const refsInComponentFile = getViewChildOrViewChildrenNames(sourceFile);
if (refsInComponentFile?.length > 0) {
const templateRefs = getTemplateReferences(template);
for (const ref of refsInComponentFile) {
if (!templateRefs.includes(ref)) {
template = template.replace(t.contents, `${startMarker}${endMarker}`);
}
}
}
else {
template = template.replace(t.contents, `${startMarker}${endMarker}`);
}
}
// templates may have changed structure from nested replaced templates
// so we need to reprocess them before the next loop.
updateTemplates(template, templates);
}
}
// template placeholders may still exist if the ng-template name is not
// present in the component. This could be because it's passed in from
// another component. In that case, we need to replace any remaining
// template placeholders with template outlets.
template = replaceRemainingPlaceholders(template);
return { migrated: template, err: undefined };
}
catch (err) {
return { migrated: template, err: err };
}
}
function getViewChildOrViewChildrenNames(sourceFile) {
const names = [];
function visit(node) {
if (ts.isDecorator(node) && ts.isCallExpression(node.expression)) {
const expr = node.expression;
if (ts.isIdentifier(expr.expression) &&
(expr.expression.text === 'ViewChild' || expr.expression.text === 'ViewChildren')) {
const firstArg = expr.arguments[0];
if (firstArg && ts.isStringLiteral(firstArg)) {
names.push(firstArg.text);
}
return;
}
}
ts.forEachChild(node, visit);
}
visit(sourceFile);
return names;
}
function getTemplateReferences(template) {
const parsed = parseTemplate(template);
if (parsed.tree === undefined) {
return [];
}
const references = [];
function visitNodes(nodes) {
for (const node of nodes) {
if (node?.name === 'ng-template') {
references.push(...node.attrs?.map((ref) => ref?.name?.slice(1)));
}
if (node.children) {
visitNodes(node.children);
}
}
}
visitNodes(parsed.tree.rootNodes);
return references;
}
function replaceRemainingPlaceholders(template) {
const pattern = '.*';
const placeholderPattern = getPlaceholder(pattern);
const replaceRegex = new RegExp(placeholderPattern, 'g');
const [placeholderStart, placeholderEnd] = placeholderPattern.split(pattern);
const placeholders = [...template.matchAll(replaceRegex)];
for (let ph of placeholders) {
const placeholder = ph[0];
const name = placeholder.slice(placeholderStart.length, placeholder.length - placeholderEnd.length);
template = template.replace(placeholder, ``);
}
return template;
}
/**
* determines if the CommonModule can be safely removed from imports
*/
function canRemoveCommonModule(template) {
const parsed = parseTemplate(template);
let removeCommonModule = false;
if (parsed.tree !== undefined) {
const visitor = new CommonCollector();
checker.visitAll(visitor, parsed.tree.rootNodes);
removeCommonModule = visitor.count === 0;
}
return removeCommonModule;
}
/**
* removes imports from template imports and import declarations
*/
function removeImports(template, node, file) {
if (template.startsWith('imports') && ts.isPropertyAssignment(node)) {
const updatedImport = updateClassImports(node, file.removeCommonModule);
return updatedImport ?? template;
}
else if (ts.isImportDeclaration(node) && checkIfShouldChange(node, file)) {
return updateImportDeclaration(node, file.removeCommonModule);
}
return template;
}
/**
* retrieves the original block of text in the template for length comparison during migration
* processing
*/
function getOriginals(etm, tmpl, offset) {
// original opening block
if (etm.el.children.length > 0) {
const childStart = etm.el.children[0].sourceSpan.start.offset - offset;
const childEnd = etm.el.children[etm.el.children.length - 1].sourceSpan.end.offset - offset;
const start = tmpl.slice(etm.el.sourceSpan.start.offset - offset, etm.el.children[0].sourceSpan.start.offset - offset);
// original closing block
const end = tmpl.slice(etm.el.children[etm.el.children.length - 1].sourceSpan.end.offset - offset, etm.el.sourceSpan.end.offset - offset);
const childLength = childEnd - childStart;
return {
start,
end,
childLength,
children: getOriginalChildren(etm.el.children, tmpl, offset),
childNodes: etm.el.children,
};
}
// self closing or no children
const start = tmpl.slice(etm.el.sourceSpan.start.offset - offset, etm.el.sourceSpan.end.offset - offset);
// original closing block
return { start, end: '', childLength: 0, children: [], childNodes: [] };
}
function getOriginalChildren(children, tmpl, offset) {
return children.map((child) => {
return tmpl.slice(child.sourceSpan.start.offset - offset, child.sourceSpan.end.offset - offset);
});
}
function isI18nTemplate(etm, i18nAttr) {
let attrCount = countAttributes(etm);
const safeToRemove = etm.el.attrs.length === attrCount + (i18nAttr !== undefined ? 1 : 0);
return etm.el.name === 'ng-template' && i18nAttr !== undefined && safeToRemove;
}
function isRemovableContainer(etm) {
let attrCount = countAttributes(etm);
const safeToRemove = etm.el.attrs.length === attrCount;
return (etm.el.name === 'ng-container' || etm.el.name === 'ng-template') && safeToRemove;
}
function countAttributes(etm) {
let attrCount = 1;
if (etm.elseAttr !== undefined) {
attrCount++;
}
if (etm.thenAttr !== undefined) {
attrCount++;
}
attrCount += etm.aliasAttrs?.aliases.size ?? 0;
attrCount += etm.aliasAttrs?.item ? 1 : 0;
attrCount += etm.forAttrs?.trackBy ? 1 : 0;
attrCount += etm.forAttrs?.forOf ? 1 : 0;
return attrCount;
}
/**
* builds the proper contents of what goes inside a given control flow block after migration
*/
function getMainBlock(etm, tmpl, offset) {
const i18nAttr = etm.el.attrs.find((x) => x.name === 'i18n');
// removable containers are ng-templates or ng-containers that no longer need to exist
// post migration
if (isRemovableContainer(etm)) {
let middle = '';
if (etm.hasChildren()) {
const { childStart, childEnd } = etm.getChildSpan(offset);
middle = tmpl.slice(childStart, childEnd);
}
else {
middle = '';
}
return { start: '', middle, end: '' };
}
else if (isI18nTemplate(etm, i18nAttr)) {
// here we're removing an ng-template used for control flow and i18n and
// converting it to an ng-container with i18n
const { childStart, childEnd } = etm.getChildSpan(offset);
return generatei18nContainer(i18nAttr, tmpl.slice(childStart, childEnd));
}
// the index of the start of the attribute adjusting for offset shift
const attrStart = etm.attr.keySpan.start.offset - 1 - offset;
// the index of the very end of the attribute value adjusted for offset shift
const valEnd = etm.getValueEnd(offset);
// the index of the children start and end span, if they exist. Otherwise use the value end.
const { childStart, childEnd } = etm.hasChildren()
? etm.getChildSpan(offset)
: { childStart: valEnd, childEnd: valEnd };
// the beginning of the updated string in the main block, for example:
let start = tmpl.slice(etm.start(offset), attrStart) + tmpl.slice(valEnd, childStart);
// the middle is the actual contents of the element
const middle = tmpl.slice(childStart, childEnd);
// the end is the closing part of the element, example:
let end = tmpl.slice(childEnd, etm.end(offset));
if (etm.shouldRemoveElseAttr()) {
// this removes a bound ngIfElse attribute that's no longer needed
// this could be on the start or end
start = start.replace(etm.getElseAttrStr(), '');
end = end.replace(etm.getElseAttrStr(), '');
}
return { start, middle, end };
}
function generateI18nMarkers(tmpl) {
let parsed = parseTemplate(tmpl);
if (parsed.tree !== undefined) {
const visitor = new i18nCollector();
checker.visitAll(visitor, parsed.tree.rootNodes);
for (const [ix, el] of visitor.elements.entries()) {
// we only care about elements with children and i18n tags
// elements without children have nothing to translate
// offset accounts for the addition of the 2 marker characters with each loop.
const offset = ix * 2;
if (el.children.length > 0) {
tmpl = addI18nMarkers(tmpl, el, offset);
}
}
}
return tmpl;
}
function addI18nMarkers(tmpl, el, offset) {
const startPos = el.children[0].sourceSpan.start.offset + offset;
const endPos = el.children[el.children.length - 1].sourceSpan.end.offset + offset;
return (tmpl.slice(0, startPos) +
startI18nMarker +
tmpl.slice(startPos, endPos) +
endI18nMarker +
tmpl.slice(endPos));
}
const selfClosingList = 'input|br|img|base|wbr|area|col|embed|hr|link|meta|param|source|track';
/**
* re-indents all the lines in the template properly post migration
*/
function formatTemplate(tmpl, templateType) {
if (tmpl.indexOf('\n') > -1) {
tmpl = generateI18nMarkers(tmpl);
// tracks if a self closing element opened without closing yet
let openSelfClosingEl = false;
// match any type of control flow block as start of string ignoring whitespace
// @if | @switch | @case | @default | @for | } @else
const openBlockRegex = /^\s*\@(if|switch|case|default|for)|^\s*\}\s\@else/;
// regex for matching an html element opening
//
||
]*\/>)[^>]*>?/;
// regex for matching an attribute string that was left open at the endof a line
// so we can ensure we have the proper indent
//
const closeAttrDoubleRegex = /^\s*([^><]|\\")*"/;
const closeAttrSingleRegex = /^\s*([^><]|\\')*'/;
// regex for matching a self closing html element that has no />
//
const selfClosingRegex = new RegExp(`^\\s*<(${selfClosingList}).+\\/?>`);
// regex for matching a self closing html element that is on multi lines
// || ]*\\/>)[^>]*$`);
// match closing block or else block
// } | } @else
const closeBlockRegex = /^\s*\}\s*$|^\s*\}\s\@else/;
// matches closing of an html element
//
const closeElRegex = /\s*<\/([a-zA-Z0-9\-_]+)\s*>/m;
// matches closing of a self closing html element when the element is on multiple lines
// [binding]="value" />
const closeMultiLineElRegex = /^\s*([a-zA-Z0-9\-_\[\]]+)?=?"?([^”<]+)?"?\s?\/>$/;
// matches closing of a self closing html element when the element is on multiple lines
// with no / in the closing: [binding]="value">
const closeSelfClosingMultiLineRegex = /^\s*([a-zA-Z0-9\-_\[\]]+)?=?"?([^”\/<]+)?"?\s?>$/;
// matches an open and close of an html element on a single line with no breaks
//
blah
const singleLineElRegex = /\s*<([a-zA-Z0-9]+)(?![^>]*\/>)[^>]*>.*<\/([a-zA-Z0-9\-_]+)\s*>/;
const lines = tmpl.split('\n');
const formatted = [];
// the indent applied during formatting
let indent = '';
// the pre-existing indent in an inline template that we'd like to preserve
let mindent = '';
let depth = 0;
let i18nDepth = 0;
let inMigratedBlock = false;
let inI18nBlock = false;
let inAttribute = false;
let isDoubleQuotes = false;
for (let [index, line] of lines.entries()) {
depth +=
[...line.matchAll(startMarkerRegex)].length - [...line.matchAll(endMarkerRegex)].length;
inMigratedBlock = depth > 0;
i18nDepth +=
[...line.matchAll(startI18nMarkerRegex)].length -
[...line.matchAll(endI18nMarkerRegex)].length;
let lineWasMigrated = false;
if (line.match(replaceMarkerRegex)) {
line = line.replace(replaceMarkerRegex, '');
lineWasMigrated = true;
}
if (line.trim() === '' &&
index !== 0 &&
index !== lines.length - 1 &&
(inMigratedBlock || lineWasMigrated) &&
!inI18nBlock &&
!inAttribute) {
// skip blank lines except if it's the first line or last line
// this preserves leading and trailing spaces if they are already present
continue;
}
// preserves the indentation of an inline template
if (templateType === 'template' && index <= 1) {
// first real line of an inline template
const ind = line.search(/\S/);
mindent = ind > -1 ? line.slice(0, ind) : '';
}
// if a block closes, an element closes, and it's not an element on a single line or the end
// of a self closing tag
if ((closeBlockRegex.test(line) ||
(closeElRegex.test(line) &&
!singleLineElRegex.test(line) &&
!closeMultiLineElRegex.test(line))) &&
indent !== '') {
// close block, reduce indent
indent = indent.slice(2);
}
// if a line ends in an unclosed attribute, we need to note that and close it later
const isOpenDoubleAttr = openAttrDoubleRegex.test(line);
const isOpenSingleAttr = openAttrSingleRegex.test(line);
if (!inAttribute && isOpenDoubleAttr) {
inAttribute = true;
isDoubleQuotes = true;
}
else if (!inAttribute && isOpenSingleAttr) {
inAttribute = true;
isDoubleQuotes = false;
}
const newLine = inI18nBlock || inAttribute
? line
: mindent + (line.trim() !== '' ? indent : '') + line.trim();
formatted.push(newLine);
if (!isOpenDoubleAttr &&
!isOpenSingleAttr &&
((inAttribute && isDoubleQuotes && closeAttrDoubleRegex.test(line)) ||
(inAttribute && !isDoubleQuotes && closeAttrSingleRegex.test(line)))) {
inAttribute = false;
}
// this matches any self closing element that actually has a />
if (closeMultiLineElRegex.test(line)) {
// multi line self closing tag
indent = indent.slice(2);
if (openSelfClosingEl) {
openSelfClosingEl = false;
}
}
// this matches a self closing element that doesn't have a / in the >
if (closeSelfClosingMultiLineRegex.test(line) && openSelfClosingEl) {
openSelfClosingEl = false;
indent = indent.slice(2);
}
// this matches an open control flow block, an open HTML element, but excludes single line
// self closing tags
if ((openBlockRegex.test(line) || openElRegex.test(line)) &&
!singleLineElRegex.test(line) &&
!selfClosingRegex.test(line) &&
!openSelfClosingRegex.test(line)) {
// open block, increase indent
indent += ' ';
}
// This is a self closing element that is definitely not fully closed and is on multiple lines
if (openSelfClosingRegex.test(line)) {
openSelfClosingEl = true;
// add to the indent for the properties on it to look nice
indent += ' ';
}
inI18nBlock = i18nDepth > 0;
}
tmpl = formatted.join('\n');
}
return tmpl;
}
/** Executes a callback on each class declaration in a file. */
function forEachClass(sourceFile, callback) {
sourceFile.forEachChild(function walk(node) {
if (ts.isClassDeclaration(node) || ts.isImportDeclaration(node)) {
callback(node);
}
node.forEachChild(walk);
});
}
const boundcase = '[ngSwitchCase]';
const switchcase = '*ngSwitchCase';
const nakedcase = 'ngSwitchCase';
const switchdefault = '*ngSwitchDefault';
const nakeddefault = 'ngSwitchDefault';
const cases = [boundcase, switchcase, nakedcase, switchdefault, nakeddefault];
/**
* Replaces structural directive ngSwitch instances with new switch.
* Returns null if the migration failed (e.g. there was a syntax error).
*/
function migrateCase(template) {
let errors = [];
let parsed = parseTemplate(template);
if (parsed.tree === undefined) {
return { migrated: template, errors, changed: false };
}
let result = template;
const visitor = new ElementCollector(cases);
checker.visitAll(visitor, parsed.tree.rootNodes);
calculateNesting(visitor, hasLineBreaks(template));
// this tracks the character shift from different lengths of blocks from
// the prior directives so as to adjust for nested block replacement during
// migration. Each block calculates length differences and passes that offset
// to the next migrating block to adjust character offsets properly.
let offset = 0;
let nestLevel = -1;
let postOffsets = [];
for (const el of visitor.elements) {
let migrateResult = { tmpl: result, offsets: { pre: 0, post: 0 } };
// applies the post offsets after closing
offset = reduceNestingOffset(el, nestLevel, offset, postOffsets);
if (el.attr.name === switchcase || el.attr.name === nakedcase || el.attr.name === boundcase) {
try {
migrateResult = migrateNgSwitchCase(el, result, offset);
}
catch (error) {
errors.push({ type: switchcase, error });
}
}
else if (el.attr.name === switchdefault || el.attr.name === nakeddefault) {
try {
migrateResult = migrateNgSwitchDefault(el, result, offset);
}
catch (error) {
errors.push({ type: switchdefault, error });
}
}
result = migrateResult.tmpl;
offset += migrateResult.offsets.pre;
postOffsets.push(migrateResult.offsets.post);
nestLevel = el.nestCount;
}
const changed = visitor.elements.length > 0;
return { migrated: result, errors, changed };
}
function migrateNgSwitchCase(etm, tmpl, offset) {
// includes the mandatory semicolon before as
const lbString = etm.hasLineBreaks ? '\n' : '';
const leadingSpace = etm.hasLineBreaks ? '' : ' ';
// ngSwitchCases with no values results into `case ()` which isn't valid, based off empty
// value we add quotes instead of generating empty case
const condition = etm.attr.value.length === 0 ? `''` : etm.attr.value;
const originals = getOriginals(etm, tmpl, offset);
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
const startBlock = `${startMarker}${leadingSpace}@case (${condition}) {${leadingSpace}${lbString}${start}`;
const endBlock = `${end}${lbString}${leadingSpace}}${endMarker}`;
const defaultBlock = startBlock + middle + endBlock;
const updatedTmpl = tmpl.slice(0, etm.start(offset)) + defaultBlock + tmpl.slice(etm.end(offset));
// this should be the difference between the starting element up to the start of the closing
// element and the mainblock sans }
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - endBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
function migrateNgSwitchDefault(etm, tmpl, offset) {
// includes the mandatory semicolon before as
const lbString = etm.hasLineBreaks ? '\n' : '';
const leadingSpace = etm.hasLineBreaks ? '' : ' ';
const originals = getOriginals(etm, tmpl, offset);
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
const startBlock = `${startMarker}${leadingSpace}@default {${leadingSpace}${lbString}${start}`;
const endBlock = `${end}${lbString}${leadingSpace}}${endMarker}`;
const defaultBlock = startBlock + middle + endBlock;
const updatedTmpl = tmpl.slice(0, etm.start(offset)) + defaultBlock + tmpl.slice(etm.end(offset));
// this should be the difference between the starting element up to the start of the closing
// element and the mainblock sans }
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - endBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
const ngfor = '*ngFor';
const nakedngfor = 'ngFor';
const fors = [ngfor, nakedngfor];
const commaSeparatedSyntax = new Map([
['(', ')'],
['{', '}'],
['[', ']'],
]);
const stringPairs = new Map([
[`"`, `"`],
[`'`, `'`],
]);
/**
* Replaces structural directive ngFor instances with new for.
* Returns null if the migration failed (e.g. there was a syntax error).
*/
function migrateFor(template) {
let errors = [];
let parsed = parseTemplate(template);
if (parsed.tree === undefined) {
return { migrated: template, errors, changed: false };
}
let result = template;
const visitor = new ElementCollector(fors);
checker.visitAll(visitor, parsed.tree.rootNodes);
calculateNesting(visitor, hasLineBreaks(template));
// this tracks the character shift from different lengths of blocks from
// the prior directives so as to adjust for nested block replacement during
// migration. Each block calculates length differences and passes that offset
// to the next migrating block to adjust character offsets properly.
let offset = 0;
let nestLevel = -1;
let postOffsets = [];
for (const el of visitor.elements) {
let migrateResult = { tmpl: result, offsets: { pre: 0, post: 0 } };
// applies the post offsets after closing
offset = reduceNestingOffset(el, nestLevel, offset, postOffsets);
try {
migrateResult = migrateNgFor(el, result, offset);
}
catch (error) {
errors.push({ type: ngfor, error });
}
result = migrateResult.tmpl;
offset += migrateResult.offsets.pre;
postOffsets.push(migrateResult.offsets.post);
nestLevel = el.nestCount;
}
const changed = visitor.elements.length > 0;
return { migrated: result, errors, changed };
}
function migrateNgFor(etm, tmpl, offset) {
if (etm.forAttrs !== undefined) {
return migrateBoundNgFor(etm, tmpl, offset);
}
return migrateStandardNgFor(etm, tmpl, offset);
}
function migrateStandardNgFor(etm, tmpl, offset) {
const aliasWithEqualRegexp = /=\s*(count|index|first|last|even|odd)/gm;
const aliasWithAsRegexp = /(count|index|first|last|even|odd)\s+as/gm;
const aliases = [];
const lbString = etm.hasLineBreaks ? '\n' : '';
const parts = getNgForParts(etm.attr.value);
const originals = getOriginals(etm, tmpl, offset);
// first portion should always be the loop definition prefixed with `let`
const condition = parts[0].replace('let ', '');
if (condition.indexOf(' as ') > -1) {
let errorMessage = `Found an aliased collection on an ngFor: "${condition}".` +
' Collection aliasing is not supported with @for.' +
' Refactor the code to remove the `as` alias and re-run the migration.';
throw new Error(errorMessage);
}
const loopVar = condition.split(' of ')[0];
let trackBy = loopVar;
let aliasedIndex = null;
let tmplPlaceholder = '';
for (let i = 1; i < parts.length; i++) {
const part = parts[i].trim();
if (part.startsWith('trackBy:')) {
// build trackby value
const trackByFn = part.replace('trackBy:', '').trim();
trackBy = `${trackByFn}($index, ${loopVar})`;
}
// template
if (part.startsWith('template:')) {
// use an alternate placeholder here to avoid conflicts
tmplPlaceholder = getPlaceholder(part.split(':')[1].trim(), PlaceholderKind.Alternate);
}
// aliases
// declared with `let myIndex = index`
if (part.match(aliasWithEqualRegexp)) {
// 'let myIndex = index' -> ['let myIndex', 'index']
const aliasParts = part.split('=');
const aliasedName = aliasParts[0].replace('let', '').trim();
const originalName = aliasParts[1].trim();
if (aliasedName !== '$' + originalName) {
// -> 'let myIndex = $index'
aliases.push(` let ${aliasedName} = $${originalName}`);
}
// if the aliased variable is the index, then we store it
if (originalName === 'index') {
// 'let myIndex' -> 'myIndex'
aliasedIndex = aliasedName;
}
}
// declared with `index as myIndex`
if (part.match(aliasWithAsRegexp)) {
// 'index as myIndex' -> ['index', 'myIndex']
const aliasParts = part.split(/\s+as\s+/);
const originalName = aliasParts[0].trim();
const aliasedName = aliasParts[1].trim();
if (aliasedName !== '$' + originalName) {
// -> 'let myIndex = $index'
aliases.push(` let ${aliasedName} = $${originalName}`);
}
// if the aliased variable is the index, then we store it
if (originalName === 'index') {
aliasedIndex = aliasedName;
}
}
}
// if an alias has been defined for the index, then the trackBy function must use it
if (aliasedIndex !== null && trackBy !== loopVar) {
// byId($index, user) -> byId(i, user)
trackBy = trackBy.replace('$index', aliasedIndex);
}
const aliasStr = aliases.length > 0 ? `;${aliases.join(';')}` : '';
let startBlock = `${startMarker}@for (${condition}; track ${trackBy}${aliasStr}) {${lbString}`;
let endBlock = `${lbString}}${endMarker}`;
let forBlock = '';
if (tmplPlaceholder !== '') {
startBlock = startBlock + tmplPlaceholder;
forBlock = startBlock + endBlock;
}
else {
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
startBlock += start;
endBlock = end + endBlock;
forBlock = startBlock + middle + endBlock;
}
const updatedTmpl = tmpl.slice(0, etm.start(offset)) + forBlock + tmpl.slice(etm.end(offset));
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - endBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
function migrateBoundNgFor(etm, tmpl, offset) {
const forAttrs = etm.forAttrs;
const aliasAttrs = etm.aliasAttrs;
const aliasMap = aliasAttrs.aliases;
const originals = getOriginals(etm, tmpl, offset);
const condition = `${aliasAttrs.item} of ${forAttrs.forOf}`;
const aliases = [];
let aliasedIndex = '$index';
for (const [key, val] of aliasMap) {
aliases.push(` let ${key.trim()} = $${val}`);
if (val.trim() === 'index') {
aliasedIndex = key;
}
}
const aliasStr = aliases.length > 0 ? `;${aliases.join(';')}` : '';
let trackBy = aliasAttrs.item;
if (forAttrs.trackBy !== '') {
// build trackby value
trackBy = `${forAttrs.trackBy.trim()}(${aliasedIndex}, ${aliasAttrs.item})`;
}
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
const startBlock = `${startMarker}@for (${condition}; track ${trackBy}${aliasStr}) {\n${start}`;
const endBlock = `${end}\n}${endMarker}`;
const forBlock = startBlock + middle + endBlock;
const updatedTmpl = tmpl.slice(0, etm.start(offset)) + forBlock + tmpl.slice(etm.end(offset));
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - endBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
function getNgForParts(expression) {
const parts = [];
const commaSeparatedStack = [];
const stringStack = [];
let current = '';
for (let i = 0; i < expression.length; i++) {
const char = expression[i];
const isInString = stringStack.length === 0;
const isInCommaSeparated = commaSeparatedStack.length === 0;
// Any semicolon is a delimiter, as well as any comma outside
// of comma-separated syntax, as long as they're outside of a string.
if (isInString &&
current.length > 0 &&
(char === ';' || (char === ',' && isInCommaSeparated))) {
parts.push(current);
current = '';
continue;
}
if (stringStack.length > 0 && stringStack[stringStack.length - 1] === char) {
stringStack.pop();
}
else if (stringPairs.has(char)) {
stringStack.push(stringPairs.get(char));
}
if (commaSeparatedSyntax.has(char)) {
commaSeparatedStack.push(commaSeparatedSyntax.get(char));
}
else if (commaSeparatedStack.length > 0 &&
commaSeparatedStack[commaSeparatedStack.length - 1] === char) {
commaSeparatedStack.pop();
}
current += char;
}
if (current.length > 0) {
parts.push(current);
}
return parts;
}
const ngif = '*ngIf';
const boundngif = '[ngIf]';
const nakedngif = 'ngIf';
const ifs = [ngif, nakedngif, boundngif];
/**
* Replaces structural directive ngif instances with new if.
* Returns null if the migration failed (e.g. there was a syntax error).
*/
function migrateIf(template) {
let errors = [];
let parsed = parseTemplate(template);
if (parsed.tree === undefined) {
return { migrated: template, errors, changed: false };
}
let result = template;
const visitor = new ElementCollector(ifs);
checker.visitAll(visitor, parsed.tree.rootNodes);
calculateNesting(visitor, hasLineBreaks(template));
// this tracks the character shift from different lengths of blocks from
// the prior directives so as to adjust for nested block replacement during
// migration. Each block calculates length differences and passes that offset
// to the next migrating block to adjust character offsets properly.
let offset = 0;
let nestLevel = -1;
let postOffsets = [];
for (const el of visitor.elements) {
let migrateResult = { tmpl: result, offsets: { pre: 0, post: 0 } };
// applies the post offsets after closing
offset = reduceNestingOffset(el, nestLevel, offset, postOffsets);
try {
migrateResult = migrateNgIf(el, result, offset);
}
catch (error) {
errors.push({ type: ngif, error });
}
result = migrateResult.tmpl;
offset += migrateResult.offsets.pre;
postOffsets.push(migrateResult.offsets.post);
nestLevel = el.nestCount;
}
const changed = visitor.elements.length > 0;
return { migrated: result, errors, changed };
}
function migrateNgIf(etm, tmpl, offset) {
const matchThen = etm.attr.value.match(/[^\w\d];?\s*then/gm);
const matchElse = etm.attr.value.match(/[^\w\d];?\s*else/gm);
if (etm.thenAttr !== undefined || etm.elseAttr !== undefined) {
// bound if then / if then else
return buildBoundIfElseBlock(etm, tmpl, offset);
}
else if (matchThen && matchThen.length > 0 && matchElse && matchElse.length > 0) {
// then else
return buildStandardIfThenElseBlock(etm, tmpl, matchThen[0], matchElse[0], offset);
}
else if (matchThen && matchThen.length > 0) {
// just then
return buildStandardIfThenBlock(etm, tmpl, matchThen[0], offset);
}
else if (matchElse && matchElse.length > 0) {
// just else
return buildStandardIfElseBlock(etm, tmpl, matchElse[0], offset);
}
return buildIfBlock(etm, tmpl, offset);
}
function buildIfBlock(etm, tmpl, offset) {
const aliasAttrs = etm.aliasAttrs;
const aliases = [...aliasAttrs.aliases.keys()];
if (aliasAttrs.item) {
aliases.push(aliasAttrs.item);
}
// includes the mandatory semicolon before as
const lbString = etm.hasLineBreaks ? '\n' : '';
let condition = etm.attr.value
.replace(' as ', '; as ')
// replace 'let' with 'as' whatever spaces are between ; and 'let'
.replace(/;\s*let/g, '; as');
if (aliases.length > 1 || (aliases.length === 1 && condition.indexOf('; as') > -1)) {
// only 1 alias allowed
throw new Error('Found more than one alias on your ngIf. Remove one of them and re-run the migration.');
}
else if (aliases.length === 1) {
condition += `; as ${aliases[0]}`;
}
const originals = getOriginals(etm, tmpl, offset);
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
const startBlock = `${startMarker}@if (${condition}) {${lbString}${start}`;
const endBlock = `${end}${lbString}}${endMarker}`;
const ifBlock = startBlock + middle + endBlock;
const updatedTmpl = tmpl.slice(0, etm.start(offset)) + ifBlock + tmpl.slice(etm.end(offset));
// this should be the difference between the starting element up to the start of the closing
// element and the mainblock sans }
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - endBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
function buildStandardIfElseBlock(etm, tmpl, elseString, offset) {
// includes the mandatory semicolon before as
const condition = etm
.getCondition()
.replace(' as ', '; as ')
// replace 'let' with 'as' whatever spaces are between ; and 'let'
.replace(/;\s*let/g, '; as');
const elsePlaceholder = getPlaceholder(etm.getTemplateName(elseString));
return buildIfElseBlock(etm, tmpl, condition, elsePlaceholder, offset);
}
function buildBoundIfElseBlock(etm, tmpl, offset) {
const aliasAttrs = etm.aliasAttrs;
const aliases = [...aliasAttrs.aliases.keys()];
if (aliasAttrs.item) {
aliases.push(aliasAttrs.item);
}
// includes the mandatory semicolon before as
let condition = etm.attr.value.replace(' as ', '; as ');
if (aliases.length > 1 || (aliases.length === 1 && condition.indexOf('; as') > -1)) {
// only 1 alias allowed
throw new Error('Found more than one alias on your ngIf. Remove one of them and re-run the migration.');
}
else if (aliases.length === 1) {
condition += `; as ${aliases[0]}`;
}
const elsePlaceholder = getPlaceholder(etm.elseAttr.value.trim());
if (etm.thenAttr !== undefined) {
const thenPlaceholder = getPlaceholder(etm.thenAttr.value.trim());
return buildIfThenElseBlock(etm, tmpl, condition, thenPlaceholder, elsePlaceholder, offset);
}
return buildIfElseBlock(etm, tmpl, condition, elsePlaceholder, offset);
}
function buildIfElseBlock(etm, tmpl, condition, elsePlaceholder, offset) {
const lbString = etm.hasLineBreaks ? '\n' : '';
const originals = getOriginals(etm, tmpl, offset);
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
const startBlock = `${startMarker}@if (${condition}) {${lbString}${start}`;
const elseBlock = `${end}${lbString}} @else {${lbString}`;
const postBlock = elseBlock + elsePlaceholder + `${lbString}}${endMarker}`;
const ifElseBlock = startBlock + middle + postBlock;
const tmplStart = tmpl.slice(0, etm.start(offset));
const tmplEnd = tmpl.slice(etm.end(offset));
const updatedTmpl = tmplStart + ifElseBlock + tmplEnd;
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - postBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
function buildStandardIfThenElseBlock(etm, tmpl, thenString, elseString, offset) {
// includes the mandatory semicolon before as
const condition = etm
.getCondition()
.replace(' as ', '; as ')
// replace 'let' with 'as' whatever spaces are between ; and 'let'
.replace(/;\s*let/g, '; as');
const thenPlaceholder = getPlaceholder(etm.getTemplateName(thenString, elseString));
const elsePlaceholder = getPlaceholder(etm.getTemplateName(elseString));
return buildIfThenElseBlock(etm, tmpl, condition, thenPlaceholder, elsePlaceholder, offset);
}
function buildStandardIfThenBlock(etm, tmpl, thenString, offset) {
// includes the mandatory semicolon before as
const condition = etm
.getCondition()
.replace(' as ', '; as ')
// replace 'let' with 'as' whatever spaces are between ; and 'let'
.replace(/;\s*let/g, '; as');
const thenPlaceholder = getPlaceholder(etm.getTemplateName(thenString));
return buildIfThenBlock(etm, tmpl, condition, thenPlaceholder, offset);
}
function buildIfThenElseBlock(etm, tmpl, condition, thenPlaceholder, elsePlaceholder, offset) {
const lbString = etm.hasLineBreaks ? '\n' : '';
const originals = getOriginals(etm, tmpl, offset);
const startBlock = `${startMarker}@if (${condition}) {${lbString}`;
const elseBlock = `${lbString}} @else {${lbString}`;
const postBlock = thenPlaceholder + elseBlock + elsePlaceholder + `${lbString}}${endMarker}`;
const ifThenElseBlock = startBlock + postBlock;
const tmplStart = tmpl.slice(0, etm.start(offset));
const tmplEnd = tmpl.slice(etm.end(offset));
const updatedTmpl = tmplStart + ifThenElseBlock + tmplEnd;
// We ignore the contents of the element on if then else.
// If there's anything there, we need to account for the length in the offset.
const pre = originals.start.length + originals.childLength - startBlock.length;
const post = originals.end.length - postBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
function buildIfThenBlock(etm, tmpl, condition, thenPlaceholder, offset) {
const lbString = etm.hasLineBreaks ? '\n' : '';
const originals = getOriginals(etm, tmpl, offset);
const startBlock = `${startMarker}@if (${condition}) {${lbString}`;
const postBlock = thenPlaceholder + `${lbString}}${endMarker}`;
const ifThenBlock = startBlock + postBlock;
const tmplStart = tmpl.slice(0, etm.start(offset));
const tmplEnd = tmpl.slice(etm.end(offset));
const updatedTmpl = tmplStart + ifThenBlock + tmplEnd;
// We ignore the contents of the element on if then else.
// If there's anything there, we need to account for the length in the offset.
const pre = originals.start.length + originals.childLength - startBlock.length;
const post = originals.end.length - postBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
const ngswitch = '[ngSwitch]';
const switches = [ngswitch];
/**
* Replaces structural directive ngSwitch instances with new switch.
* Returns null if the migration failed (e.g. there was a syntax error).
*/
function migrateSwitch(template) {
let errors = [];
let parsed = parseTemplate(template);
if (parsed.tree === undefined) {
return { migrated: template, errors, changed: false };
}
let result = template;
const visitor = new ElementCollector(switches);
checker.visitAll(visitor, parsed.tree.rootNodes);
calculateNesting(visitor, hasLineBreaks(template));
// this tracks the character shift from different lengths of blocks from
// the prior directives so as to adjust for nested block replacement during
// migration. Each block calculates length differences and passes that offset
// to the next migrating block to adjust character offsets properly.
let offset = 0;
let nestLevel = -1;
let postOffsets = [];
for (const el of visitor.elements) {
let migrateResult = { tmpl: result, offsets: { pre: 0, post: 0 } };
// applies the post offsets after closing
offset = reduceNestingOffset(el, nestLevel, offset, postOffsets);
if (el.attr.name === ngswitch) {
try {
migrateResult = migrateNgSwitch(el, result, offset);
}
catch (error) {
errors.push({ type: ngswitch, error });
}
}
result = migrateResult.tmpl;
offset += migrateResult.offsets.pre;
postOffsets.push(migrateResult.offsets.post);
nestLevel = el.nestCount;
}
const changed = visitor.elements.length > 0;
return { migrated: result, errors, changed };
}
function assertValidSwitchStructure(children) {
for (const child of children) {
if (child instanceof checker.Text && child.value.trim() !== '') {
throw new Error(`Text node: "${child.value}" would result in invalid migrated @switch block structure. ` +
`@switch can only have @case or @default as children.`);
}
else if (child instanceof checker.Element) {
let hasCase = false;
for (const attr of child.attrs) {
if (cases.includes(attr.name)) {
hasCase = true;
}
}
if (!hasCase) {
throw new Error(`Element node: "${child.name}" would result in invalid migrated @switch block structure. ` +
`@switch can only have @case or @default as children.`);
}
}
}
}
function migrateNgSwitch(etm, tmpl, offset) {
const lbString = etm.hasLineBreaks ? '\n' : '';
const condition = etm.attr.value;
const originals = getOriginals(etm, tmpl, offset);
assertValidSwitchStructure(originals.childNodes);
const { start, middle, end } = getMainBlock(etm, tmpl, offset);
const startBlock = `${startMarker}${start}${lbString}@switch (${condition}) {`;
const endBlock = `}${lbString}${end}${endMarker}`;
const switchBlock = startBlock + middle + endBlock;
const updatedTmpl = tmpl.slice(0, etm.start(offset)) + switchBlock + tmpl.slice(etm.end(offset));
// this should be the difference between the starting element up to the start of the closing
// element and the mainblock sans }
const pre = originals.start.length - startBlock.length;
const post = originals.end.length - endBlock.length;
return { tmpl: updatedTmpl, offsets: { pre, post } };
}
/**
* Actually migrates a given template to the new syntax
*/
function migrateTemplate(template, templateType, node, file, format = true, analyzedFiles) {
let errors = [];
let migrated = template;
if (templateType === 'template' || templateType === 'templateUrl') {
const ifResult = migrateIf(template);
const forResult = migrateFor(ifResult.migrated);
const switchResult = migrateSwitch(forResult.migrated);
if (switchResult.errors.length > 0) {
return { migrated: template, errors: switchResult.errors };
}
const caseResult = migrateCase(switchResult.migrated);
const templateResult = processNgTemplates(caseResult.migrated, file.sourceFile);
if (templateResult.err !== undefined) {
return { migrated: template, errors: [{ type: 'template', error: templateResult.err }] };
}
migrated = templateResult.migrated;
const changed = ifResult.changed || forResult.changed || switchResult.changed || caseResult.changed;
if (changed) {
// determine if migrated template is a valid structure
// if it is not, fail out
const errors = validateMigratedTemplate(migrated, file.sourceFile.fileName);
if (errors.length > 0) {
return { migrated: template, errors };
}
}
if (format && changed) {
migrated = formatTemplate(migrated, templateType);
}
const markerRegex = new RegExp(`${startMarker}|${endMarker}|${startI18nMarker}|${endI18nMarker}`, 'gm');
migrated = migrated.replace(markerRegex, '');
file.removeCommonModule = canRemoveCommonModule(template);
file.canRemoveImports = true;
// when migrating an external template, we have to pass back
// whether it's safe to remove the CommonModule to the
// original component class source file
if (templateType === 'templateUrl' &&
analyzedFiles !== null &&
analyzedFiles.has(file.sourceFile.fileName)) {
const componentFile = analyzedFiles.get(file.sourceFile.fileName);
componentFile.getSortedRanges();
// we have already checked the template file to see if it is safe to remove the imports
// and common module. This check is passed off to the associated .ts file here so
// the class knows whether it's safe to remove from the template side.
componentFile.removeCommonModule = file.removeCommonModule;
componentFile.canRemoveImports = file.canRemoveImports;
// At this point, we need to verify the component class file doesn't have any other imports
// that prevent safe removal of common module. It could be that there's an associated ngmodule
// and in that case we can't safely remove the common module import.
componentFile.verifyCanRemoveImports();
}
file.verifyCanRemoveImports();
errors = [
...ifResult.errors,
...forResult.errors,
...switchResult.errors,
...caseResult.errors,
];
}
else if (file.canRemoveImports) {
migrated = removeImports(template, node, file);
}
return { migrated, errors };
}
function migrate(options) {
return async (tree, context) => {
const basePath = process.cwd();
const pathToMigrate = compiler_host.normalizePath(p.join(basePath, options.path));
let allPaths = [];
if (pathToMigrate.trim() !== '') {
allPaths.push(pathToMigrate);
}
if (!allPaths.length) {
throw new schematics.SchematicsException('Could not find any tsconfig file. Cannot run the control flow migration.');
}
let errors = [];
for (const tsconfigPath of allPaths) {
const migrateErrors = runControlFlowMigration(tree, tsconfigPath, basePath, pathToMigrate, options);
errors = [...errors, ...migrateErrors];
}
if (errors.length > 0) {
context.logger.warn(`WARNING: ${errors.length} errors occurred during your migration:\n`);
errors.forEach((err) => {
context.logger.warn(err);
});
}
};
}
function runControlFlowMigration(tree, tsconfigPath, basePath, pathToMigrate, schematicOptions) {
if (schematicOptions.path.startsWith('..')) {
throw new schematics.SchematicsException('Cannot run control flow migration outside of the current project.');
}
const program = compiler_host.createMigrationProgram(tree, tsconfigPath, basePath);
const sourceFiles = program
.getSourceFiles()
.filter((sourceFile) => sourceFile.fileName.startsWith(pathToMigrate) &&
compiler_host.canMigrateFile(basePath, sourceFile, program));
if (sourceFiles.length === 0) {
throw new schematics.SchematicsException(`Could not find any files to migrate under the path ${pathToMigrate}. Cannot run the control flow migration.`);
}
const analysis = new Map();
const migrateErrors = new Map();
for (const sourceFile of sourceFiles) {
analyze(sourceFile, analysis);
}
// sort files with .html files first
// this ensures class files know if it's safe to remove CommonModule
const paths = sortFilePaths([...analysis.keys()]);
for (const path of paths) {
const file = analysis.get(path);
const ranges = file.getSortedRanges();
const relativePath = p.relative(basePath, path);
const content = tree.readText(relativePath);
const update = tree.beginUpdate(relativePath);
for (const { start, end, node, type } of ranges) {
const template = content.slice(start, end);
const length = (end ?? content.length) - start;
const { migrated, errors } = migrateTemplate(template, type, node, file, schematicOptions.format, analysis);
if (migrated !== null) {
update.remove(start, length);
update.insertLeft(start, migrated);
}
if (errors.length > 0) {
migrateErrors.set(path, errors);
}
}
tree.commitUpdate(update);
}
const errorList = [];
for (let [template, errors] of migrateErrors) {
errorList.push(generateErrorMessage(template, errors));
}
return errorList;
}
function sortFilePaths(names) {
names.sort((a, _) => (a.endsWith('.html') ? -1 : 0));
return names;
}
function generateErrorMessage(path, errors) {
let errorMessage = `Template "${path}" encountered ${errors.length} errors during migration:\n`;
errorMessage += errors.map((e) => ` - ${e.type}: ${e.error}\n`);
return errorMessage;
}
exports.migrate = migrate;