Charles Lyding cfbd6e81fb refactor(@schematics/angular): use type guard based narrowing in ast-utils
By leveraging TypeScript's AST type guards, function parameter assumptions and casting can be removed.  Many of these cases caused errors when enabling TypeScript's strict option. This is preliminary work to support enabling full TypeScript strict mode within the project.
2020-06-13 20:08:59 +02:00

754 lines
25 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import * as ts from '../third_party/github.com/Microsoft/TypeScript/lib/typescript';
import { Change, InsertChange, NoopChange } from './change';
/**
* Add Import `import { symbolName } from fileName` if the import doesn't exit
* already. Assumes fileToEdit can be resolved and accessed.
* @param fileToEdit (file we want to add import to)
* @param symbolName (item to import)
* @param fileName (path to the file)
* @param isDefault (if true, import follows style for importing default exports)
* @return Change
*/
export function insertImport(source: ts.SourceFile, fileToEdit: string, symbolName: string,
fileName: string, isDefault = false): Change {
const rootNode = source;
const allImports = findNodes(rootNode, ts.SyntaxKind.ImportDeclaration);
// get nodes that map to import statements from the file fileName
const relevantImports = allImports.filter(node => {
// StringLiteral of the ImportDeclaration is the import file (fileName in this case).
const importFiles = node.getChildren()
.filter(ts.isStringLiteral)
.map(n => n.text);
return importFiles.filter(file => file === fileName).length === 1;
});
if (relevantImports.length > 0) {
let importsAsterisk = false;
// imports from import file
const imports: ts.Node[] = [];
relevantImports.forEach(n => {
Array.prototype.push.apply(imports, findNodes(n, ts.SyntaxKind.Identifier));
if (findNodes(n, ts.SyntaxKind.AsteriskToken).length > 0) {
importsAsterisk = true;
}
});
// if imports * from fileName, don't add symbolName
if (importsAsterisk) {
return new NoopChange();
}
const importTextNodes = imports.filter(n => (n as ts.Identifier).text === symbolName);
// insert import if it's not there
if (importTextNodes.length === 0) {
const fallbackPos =
findNodes(relevantImports[0], ts.SyntaxKind.CloseBraceToken)[0].getStart() ||
findNodes(relevantImports[0], ts.SyntaxKind.FromKeyword)[0].getStart();
return insertAfterLastOccurrence(imports, `, ${symbolName}`, fileToEdit, fallbackPos);
}
return new NoopChange();
}
// no such import declaration exists
const useStrict = findNodes(rootNode, ts.isStringLiteral)
.filter((n) => n.text === 'use strict');
let fallbackPos = 0;
if (useStrict.length > 0) {
fallbackPos = useStrict[0].end;
}
const open = isDefault ? '' : '{ ';
const close = isDefault ? '' : ' }';
// if there are no imports or 'use strict' statement, insert import at beginning of file
const insertAtBeginning = allImports.length === 0 && useStrict.length === 0;
const separator = insertAtBeginning ? '' : ';\n';
const toInsert = `${separator}import ${open}${symbolName}${close}` +
` from '${fileName}'${insertAtBeginning ? ';\n' : ''}`;
return insertAfterLastOccurrence(
allImports,
toInsert,
fileToEdit,
fallbackPos,
ts.SyntaxKind.StringLiteral,
);
}
/**
* Find all nodes from the AST in the subtree of node of SyntaxKind kind.
* @param node
* @param kind
* @param max The maximum number of items to return.
* @param recursive Continue looking for nodes of kind recursive until end
* the last child even when node of kind has been found.
* @return all nodes of kind, or [] if none is found
*/
export function findNodes(node: ts.Node, kind: ts.SyntaxKind, max?: number, recursive?: boolean): ts.Node[];
/**
* Find all nodes from the AST in the subtree that satisfy a type guard.
* @param node
* @param guard
* @param max The maximum number of items to return.
* @param recursive Continue looking for nodes of kind recursive until end
* the last child even when node of kind has been found.
* @return all nodes that satisfy the type guard, or [] if none is found
*/
export function findNodes<T extends ts.Node>(node: ts.Node, guard: (node: ts.Node) => node is T, max?: number, recursive?: boolean): T[];
export function findNodes<T extends ts.Node>(
node: ts.Node,
kindOrGuard: ts.SyntaxKind | ((node: ts.Node) => node is T),
max = Infinity,
recursive = false,
): T[] {
if (!node || max == 0) {
return [];
}
const test =
typeof kindOrGuard === 'function'
? kindOrGuard
: (node: ts.Node): node is T => node.kind === kindOrGuard;
const arr: T[] = [];
if (test(node)) {
arr.push(node);
max--;
}
if (max > 0 && (recursive || !test(node))) {
for (const child of node.getChildren()) {
findNodes(child, test, max).forEach((node) => {
if (max > 0) {
arr.push(node);
}
max--;
});
if (max <= 0) {
break;
}
}
}
return arr;
}
/**
* Get all the nodes from a source.
* @param sourceFile The source file object.
* @returns {Observable<ts.Node>} An observable of all the nodes in the source.
*/
export function getSourceNodes(sourceFile: ts.SourceFile): ts.Node[] {
const nodes: ts.Node[] = [sourceFile];
const result = [];
while (nodes.length > 0) {
const node = nodes.shift();
if (node) {
result.push(node);
if (node.getChildCount(sourceFile) >= 0) {
nodes.unshift(...node.getChildren());
}
}
}
return result;
}
export function findNode(node: ts.Node, kind: ts.SyntaxKind, text: string): ts.Node | null {
if (node.kind === kind && node.getText() === text) {
// throw new Error(node.getText());
return node;
}
let foundNode: ts.Node | null = null;
ts.forEachChild(node, childNode => {
foundNode = foundNode || findNode(childNode, kind, text);
});
return foundNode;
}
/**
* Helper for sorting nodes.
* @return function to sort nodes in increasing order of position in sourceFile
*/
function nodesByPosition(first: ts.Node, second: ts.Node): number {
return first.getStart() - second.getStart();
}
/**
* Insert `toInsert` after the last occurence of `ts.SyntaxKind[nodes[i].kind]`
* or after the last of occurence of `syntaxKind` if the last occurence is a sub child
* of ts.SyntaxKind[nodes[i].kind] and save the changes in file.
*
* @param nodes insert after the last occurence of nodes
* @param toInsert string to insert
* @param file file to insert changes into
* @param fallbackPos position to insert if toInsert happens to be the first occurence
* @param syntaxKind the ts.SyntaxKind of the subchildren to insert after
* @return Change instance
* @throw Error if toInsert is first occurence but fall back is not set
*/
export function insertAfterLastOccurrence(nodes: ts.Node[],
toInsert: string,
file: string,
fallbackPos: number,
syntaxKind?: ts.SyntaxKind): Change {
let lastItem: ts.Node | undefined;
for (const node of nodes) {
if (!lastItem || lastItem.getStart() < node.getStart()) {
lastItem = node;
}
}
if (syntaxKind && lastItem) {
lastItem = findNodes(lastItem, syntaxKind).sort(nodesByPosition).pop();
}
if (!lastItem && fallbackPos == undefined) {
throw new Error(`tried to insert ${toInsert} as first occurence with no fallback position`);
}
const lastItemPosition: number = lastItem ? lastItem.getEnd() : fallbackPos;
return new InsertChange(file, lastItemPosition, toInsert);
}
export function getContentOfKeyLiteral(_source: ts.SourceFile, node: ts.Node): string | null {
if (node.kind == ts.SyntaxKind.Identifier) {
return (node as ts.Identifier).text;
} else if (node.kind == ts.SyntaxKind.StringLiteral) {
return (node as ts.StringLiteral).text;
} else {
return null;
}
}
function _angularImportsFromNode(node: ts.ImportDeclaration,
_sourceFile: ts.SourceFile): {[name: string]: string} {
const ms = node.moduleSpecifier;
let modulePath: string;
switch (ms.kind) {
case ts.SyntaxKind.StringLiteral:
modulePath = (ms as ts.StringLiteral).text;
break;
default:
return {};
}
if (!modulePath.startsWith('@angular/')) {
return {};
}
if (node.importClause) {
if (node.importClause.name) {
// This is of the form `import Name from 'path'`. Ignore.
return {};
} else if (node.importClause.namedBindings) {
const nb = node.importClause.namedBindings;
if (nb.kind == ts.SyntaxKind.NamespaceImport) {
// This is of the form `import * as name from 'path'`. Return `name.`.
return {
[(nb as ts.NamespaceImport).name.text + '.']: modulePath,
};
} else {
// This is of the form `import {a,b,c} from 'path'`
const namedImports = nb as ts.NamedImports;
return namedImports.elements
.map((is: ts.ImportSpecifier) => is.propertyName ? is.propertyName.text : is.name.text)
.reduce((acc: {[name: string]: string}, curr: string) => {
acc[curr] = modulePath;
return acc;
}, {});
}
}
return {};
} else {
// This is of the form `import 'path';`. Nothing to do.
return {};
}
}
export function getDecoratorMetadata(source: ts.SourceFile, identifier: string,
module: string): ts.Node[] {
const angularImports = findNodes(source, ts.isImportDeclaration)
.map((node) => _angularImportsFromNode(node, source))
.reduce((acc, current) => {
for (const key of Object.keys(current)) {
acc[key] = current[key];
}
return acc;
}, {});
return getSourceNodes(source)
.filter(node => {
return node.kind == ts.SyntaxKind.Decorator
&& (node as ts.Decorator).expression.kind == ts.SyntaxKind.CallExpression;
})
.map(node => (node as ts.Decorator).expression as ts.CallExpression)
.filter(expr => {
if (expr.expression.kind == ts.SyntaxKind.Identifier) {
const id = expr.expression as ts.Identifier;
return id.text == identifier && angularImports[id.text] === module;
} else if (expr.expression.kind == ts.SyntaxKind.PropertyAccessExpression) {
// This covers foo.NgModule when importing * as foo.
const paExpr = expr.expression as ts.PropertyAccessExpression;
// If the left expression is not an identifier, just give up at that point.
if (paExpr.expression.kind !== ts.SyntaxKind.Identifier) {
return false;
}
const id = paExpr.name.text;
const moduleId = (paExpr.expression as ts.Identifier).text;
return id === identifier && (angularImports[moduleId + '.'] === module);
}
return false;
})
.filter(expr => expr.arguments[0]
&& expr.arguments[0].kind == ts.SyntaxKind.ObjectLiteralExpression)
.map(expr => expr.arguments[0] as ts.ObjectLiteralExpression);
}
function findClassDeclarationParent(node: ts.Node): ts.ClassDeclaration|undefined {
if (ts.isClassDeclaration(node)) {
return node;
}
return node.parent && findClassDeclarationParent(node.parent);
}
/**
* Given a source file with @NgModule class(es), find the name of the first @NgModule class.
*
* @param source source file containing one or more @NgModule
* @returns the name of the first @NgModule, or `undefined` if none is found
*/
export function getFirstNgModuleName(source: ts.SourceFile): string|undefined {
// First, find the @NgModule decorators.
const ngModulesMetadata = getDecoratorMetadata(source, 'NgModule', '@angular/core');
if (ngModulesMetadata.length === 0) {
return undefined;
}
// Then walk parent pointers up the AST, looking for the ClassDeclaration parent of the NgModule
// metadata.
const moduleClass = findClassDeclarationParent(ngModulesMetadata[0]);
if (!moduleClass || !moduleClass.name) {
return undefined;
}
// Get the class name of the module ClassDeclaration.
return moduleClass.name.text;
}
export function getMetadataField(
node: ts.ObjectLiteralExpression,
metadataField: string,
): ts.ObjectLiteralElement[] {
return node.properties
.filter(ts.isPropertyAssignment)
// Filter out every fields that's not "metadataField". Also handles string literals
// (but not expressions).
.filter(({ name }) => {
return (ts.isIdentifier(name) || ts.isStringLiteral(name))
&& name.getText() === metadataField;
});
}
export function addSymbolToNgModuleMetadata(
source: ts.SourceFile,
ngModulePath: string,
metadataField: string,
symbolName: string,
importPath: string | null = null,
): Change[] {
const nodes = getDecoratorMetadata(source, 'NgModule', '@angular/core');
let node: any = nodes[0]; // tslint:disable-line:no-any
// Find the decorator declaration.
if (!node) {
return [];
}
// Get all the children property assignment of object literals.
const matchingProperties = getMetadataField(
node as ts.ObjectLiteralExpression,
metadataField,
);
// Get the last node of the array literal.
if (!matchingProperties) {
return [];
}
if (matchingProperties.length == 0) {
// We haven't found the field in the metadata declaration. Insert a new field.
const expr = node as ts.ObjectLiteralExpression;
let position: number;
let toInsert: string;
if (expr.properties.length == 0) {
position = expr.getEnd() - 1;
toInsert = ` ${metadataField}: [${symbolName}]\n`;
} else {
node = expr.properties[expr.properties.length - 1];
position = node.getEnd();
// Get the indentation of the last element, if any.
const text = node.getFullText(source);
const matches = text.match(/^\r?\n\s*/);
if (matches && matches.length > 0) {
toInsert = `,${matches[0]}${metadataField}: [${symbolName}]`;
} else {
toInsert = `, ${metadataField}: [${symbolName}]`;
}
}
if (importPath !== null) {
return [
new InsertChange(ngModulePath, position, toInsert),
insertImport(source, ngModulePath, symbolName.replace(/\..*$/, ''), importPath),
];
} else {
return [new InsertChange(ngModulePath, position, toInsert)];
}
}
const assignment = matchingProperties[0] as ts.PropertyAssignment;
// If it's not an array, nothing we can do really.
if (assignment.initializer.kind !== ts.SyntaxKind.ArrayLiteralExpression) {
return [];
}
const arrLiteral = assignment.initializer as ts.ArrayLiteralExpression;
if (arrLiteral.elements.length == 0) {
// Forward the property.
node = arrLiteral;
} else {
node = arrLiteral.elements;
}
if (!node) {
// tslint:disable-next-line: no-console
console.error('No app module found. Please add your new class to your component.');
return [];
}
if (Array.isArray(node)) {
const nodeArray = node as {} as Array<ts.Node>;
const symbolsArray = nodeArray.map(node => node.getText());
if (symbolsArray.includes(symbolName)) {
return [];
}
node = node[node.length - 1];
}
let toInsert: string;
let position = node.getEnd();
if (node.kind == ts.SyntaxKind.ObjectLiteralExpression) {
// We haven't found the field in the metadata declaration. Insert a new
// field.
const expr = node as ts.ObjectLiteralExpression;
if (expr.properties.length == 0) {
position = expr.getEnd() - 1;
toInsert = ` ${symbolName}\n`;
} else {
// Get the indentation of the last element, if any.
const text = node.getFullText(source);
if (text.match(/^\r?\r?\n/)) {
toInsert = `,${text.match(/^\r?\n\s*/)[0]}${symbolName}`;
} else {
toInsert = `, ${symbolName}`;
}
}
} else if (node.kind == ts.SyntaxKind.ArrayLiteralExpression) {
// We found the field but it's empty. Insert it just before the `]`.
position--;
toInsert = `${symbolName}`;
} else {
// Get the indentation of the last element, if any.
const text = node.getFullText(source);
if (text.match(/^\r?\n/)) {
toInsert = `,${text.match(/^\r?\n(\r?)\s*/)[0]}${symbolName}`;
} else {
toInsert = `, ${symbolName}`;
}
}
if (importPath !== null) {
return [
new InsertChange(ngModulePath, position, toInsert),
insertImport(source, ngModulePath, symbolName.replace(/\..*$/, ''), importPath),
];
}
return [new InsertChange(ngModulePath, position, toInsert)];
}
/**
* Custom function to insert a declaration (component, pipe, directive)
* into NgModule declarations. It also imports the component.
*/
export function addDeclarationToModule(source: ts.SourceFile,
modulePath: string, classifiedName: string,
importPath: string): Change[] {
return addSymbolToNgModuleMetadata(
source, modulePath, 'declarations', classifiedName, importPath);
}
/**
* Custom function to insert an NgModule into NgModule imports. It also imports the module.
*/
export function addImportToModule(source: ts.SourceFile,
modulePath: string, classifiedName: string,
importPath: string): Change[] {
return addSymbolToNgModuleMetadata(source, modulePath, 'imports', classifiedName, importPath);
}
/**
* Custom function to insert a provider into NgModule. It also imports it.
*/
export function addProviderToModule(source: ts.SourceFile,
modulePath: string, classifiedName: string,
importPath: string): Change[] {
return addSymbolToNgModuleMetadata(source, modulePath, 'providers', classifiedName, importPath);
}
/**
* Custom function to insert an export into NgModule. It also imports it.
*/
export function addExportToModule(source: ts.SourceFile,
modulePath: string, classifiedName: string,
importPath: string): Change[] {
return addSymbolToNgModuleMetadata(source, modulePath, 'exports', classifiedName, importPath);
}
/**
* Custom function to insert an export into NgModule. It also imports it.
*/
export function addBootstrapToModule(source: ts.SourceFile,
modulePath: string, classifiedName: string,
importPath: string): Change[] {
return addSymbolToNgModuleMetadata(source, modulePath, 'bootstrap', classifiedName, importPath);
}
/**
* Custom function to insert an entryComponent into NgModule. It also imports it.
* @deprecated - Since version 9.0.0 with Ivy, entryComponents is no longer necessary.
*/
export function addEntryComponentToModule(source: ts.SourceFile,
modulePath: string, classifiedName: string,
importPath: string): Change[] {
return addSymbolToNgModuleMetadata(
source, modulePath,
'entryComponents', classifiedName, importPath,
);
}
/**
* Determine if an import already exists.
*/
export function isImported(source: ts.SourceFile,
classifiedName: string,
importPath: string): boolean {
const allNodes = getSourceNodes(source);
const matchingNodes = allNodes
.filter(ts.isImportDeclaration)
.filter(
(imp) => ts.isStringLiteral(imp.moduleSpecifier) && imp.moduleSpecifier.text === importPath,
)
.filter((imp) => {
if (!imp.importClause) {
return false;
}
const nodes = findNodes(imp.importClause, ts.isImportSpecifier).filter(
(n) => n.getText() === classifiedName,
);
return nodes.length > 0;
});
return matchingNodes.length > 0;
}
/**
* This function returns the name of the environment export
* whether this export is aliased or not. If the environment file
* is not imported, then it will return `null`.
*/
export function getEnvironmentExportName(source: ts.SourceFile): string | null {
// Initial value is `null` as we don't know yet if the user
// has imported `environment` into the root module or not.
let environmentExportName: string | null = null;
const allNodes = getSourceNodes(source);
allNodes
.filter(ts.isImportDeclaration)
.filter(
(declaration) =>
declaration.moduleSpecifier.kind === ts.SyntaxKind.StringLiteral &&
declaration.importClause !== undefined,
)
.map((declaration) =>
// If `importClause` property is defined then the first
// child will be `NamedImports` object (or `namedBindings`).
(declaration.importClause as ts.ImportClause).getChildAt(0),
)
// Find those `NamedImports` object that contains `environment` keyword
// in its text. E.g. `{ environment as env }`.
.filter(ts.isNamedImports)
.filter((namedImports) => namedImports.getText().includes('environment'))
.forEach((namedImports) => {
for (const specifier of namedImports.elements) {
// `propertyName` is defined if the specifier
// has an aliased import.
const name = specifier.propertyName || specifier.name;
// Find specifier that contains `environment` keyword in its text.
// Whether it's `environment` or `environment as env`.
if (name.text.includes('environment')) {
environmentExportName = specifier.name.text;
}
}
});
return environmentExportName;
}
/**
* Returns the RouterModule declaration from NgModule metadata, if any.
*/
export function getRouterModuleDeclaration(source: ts.SourceFile): ts.Expression | undefined {
const result = getDecoratorMetadata(source, 'NgModule', '@angular/core') as ts.Node[];
const node = result[0] as ts.ObjectLiteralExpression;
const matchingProperties = getMetadataField(node, 'imports');
if (!matchingProperties) {
return;
}
const assignment = matchingProperties[0] as ts.PropertyAssignment;
if (assignment.initializer.kind !== ts.SyntaxKind.ArrayLiteralExpression) {
return;
}
const arrLiteral = assignment.initializer as ts.ArrayLiteralExpression;
return arrLiteral.elements
.filter(el => el.kind === ts.SyntaxKind.CallExpression)
.find(el => (el as ts.Identifier).getText().startsWith('RouterModule'));
}
/**
* Adds a new route declaration to a router module (i.e. has a RouterModule declaration)
*/
export function addRouteDeclarationToModule(
source: ts.SourceFile,
fileToAdd: string,
routeLiteral: string,
): Change {
const routerModuleExpr = getRouterModuleDeclaration(source);
if (!routerModuleExpr) {
throw new Error(`Couldn't find a route declaration in ${fileToAdd}.`);
}
const scopeConfigMethodArgs = (routerModuleExpr as ts.CallExpression).arguments;
if (!scopeConfigMethodArgs.length) {
const { line } = source.getLineAndCharacterOfPosition(routerModuleExpr.getStart());
throw new Error(
`The router module method doesn't have arguments ` +
`at line ${line} in ${fileToAdd}`,
);
}
let routesArr: ts.ArrayLiteralExpression | undefined;
const routesArg = scopeConfigMethodArgs[0];
// Check if the route declarations array is
// an inlined argument of RouterModule or a standalone variable
if (ts.isArrayLiteralExpression(routesArg)) {
routesArr = routesArg;
} else {
const routesVarName = routesArg.getText();
let routesVar;
if (routesArg.kind === ts.SyntaxKind.Identifier) {
routesVar = source.statements
.filter(ts.isVariableStatement)
.find((v) => {
return v.declarationList.declarations[0].name.getText() === routesVarName;
});
}
if (!routesVar) {
const { line } = source.getLineAndCharacterOfPosition(routesArg.getStart());
throw new Error(
`No route declaration array was found that corresponds ` +
`to router module at line ${line} in ${fileToAdd}`,
);
}
routesArr = findNodes(routesVar, ts.SyntaxKind.ArrayLiteralExpression, 1)[0] as ts.ArrayLiteralExpression;
}
const occurrencesCount = routesArr.elements.length;
const text = routesArr.getFullText(source);
let route: string = routeLiteral;
let insertPos = routesArr.elements.pos;
if (occurrencesCount > 0) {
const lastRouteLiteral = [...routesArr.elements].pop() as ts.Expression;
const lastRouteIsWildcard = ts.isObjectLiteralExpression(lastRouteLiteral)
&& lastRouteLiteral
.properties
.some(n => (
ts.isPropertyAssignment(n)
&& ts.isIdentifier(n.name)
&& n.name.text === 'path'
&& ts.isStringLiteral(n.initializer)
&& n.initializer.text === '**'
));
const indentation = text.match(/\r?\n(\r?)\s*/) || [];
const routeText = `${indentation[0] || ' '}${routeLiteral}`;
// Add the new route before the wildcard route
// otherwise we'll always redirect to the wildcard route
if (lastRouteIsWildcard) {
insertPos = lastRouteLiteral.pos;
route = `${routeText},`;
} else {
insertPos = lastRouteLiteral.end;
route = `,${routeText}`;
}
}
return new InsertChange(fileToAdd, insertPos, route);
}