@angular-devkit/build-optimizer
Version:
Angular Build Optimizer
189 lines (188 loc) • 7.58 kB
JavaScript
;
/**
* @license
* Copyright Google LLC 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
*/
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
__setModuleDefault(result, mod);
return result;
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.getPrefixClassesTransformer = exports.testPrefixClasses = void 0;
const ts = __importStar(require("typescript"));
const ast_utils_1 = require("../helpers/ast-utils");
function testPrefixClasses(content) {
const exportVarSetter = /(?:export )?(?:var|const)\s+(?:\S+)\s*=\s*/;
const multiLineComment = /\s*(?:\/\*[\s\S]*?\*\/)?\s*/;
const newLine = /\s*\r?\n\s*/;
const regexes = [
[
/^/,
exportVarSetter,
multiLineComment,
/\(/,
multiLineComment,
/\s*function \(\) {/,
newLine,
multiLineComment,
/function (?:\S+)\([^)]*\) \{/,
newLine,
],
[
/^/,
exportVarSetter,
multiLineComment,
/\(/,
multiLineComment,
/\s*function \(_super\) {/,
newLine,
/\S*\.?__extends\(\S+, _super\);/,
],
].map((arr) => new RegExp(arr.map((x) => x.source).join(''), 'm'));
return regexes.some((regex) => regex.test(content));
}
exports.testPrefixClasses = testPrefixClasses;
const superParameterName = '_super';
const extendsHelperName = '__extends';
function getPrefixClassesTransformer() {
return (context) => {
const transformer = (sf) => {
const visitor = (node) => {
// Add pure comment to downleveled classes.
if (ts.isVariableStatement(node) && isDownleveledClass(node)) {
const varDecl = node.declarationList.declarations[0];
const varInitializer = varDecl.initializer;
// Update node with the pure comment before the variable declaration initializer.
const newNode = ts.updateVariableStatement(node, node.modifiers, ts.updateVariableDeclarationList(node.declarationList, [
ts.updateVariableDeclaration(varDecl, varDecl.name, varDecl.type, (0, ast_utils_1.addPureComment)(varInitializer)),
]));
// Replace node with modified one.
return ts.visitEachChild(newNode, visitor, context);
}
// Otherwise return node as is.
return ts.visitEachChild(node, visitor, context);
};
return ts.visitEachChild(sf, visitor, context);
};
return transformer;
};
}
exports.getPrefixClassesTransformer = getPrefixClassesTransformer;
// Determine if a node matched the structure of a downleveled TS class.
function isDownleveledClass(node) {
if (!ts.isVariableStatement(node)) {
return false;
}
if (node.declarationList.declarations.length !== 1) {
return false;
}
const variableDeclaration = node.declarationList.declarations[0];
if (!ts.isIdentifier(variableDeclaration.name) || !variableDeclaration.initializer) {
return false;
}
let potentialClass = variableDeclaration.initializer;
// TS 2.3 has an unwrapped class IIFE
// TS 2.4 uses a function expression wrapper
// TS 2.5 uses an arrow function wrapper
if (ts.isParenthesizedExpression(potentialClass)) {
potentialClass = potentialClass.expression;
}
if (!ts.isCallExpression(potentialClass) || potentialClass.arguments.length > 1) {
return false;
}
let wrapperBody;
if (ts.isFunctionExpression(potentialClass.expression)) {
wrapperBody = potentialClass.expression.body;
}
else if (ts.isArrowFunction(potentialClass.expression) &&
ts.isBlock(potentialClass.expression.body)) {
wrapperBody = potentialClass.expression.body;
}
else {
return false;
}
if (wrapperBody.statements.length === 0) {
return false;
}
const functionExpression = potentialClass.expression;
const functionStatements = wrapperBody.statements;
// need a minimum of two for a function declaration and return statement
if (functionStatements.length < 2) {
return false;
}
const firstStatement = functionStatements[0];
// find return statement - may not be last statement
let returnStatement;
for (let i = functionStatements.length - 1; i > 0; i--) {
if (ts.isReturnStatement(functionStatements[i])) {
returnStatement = functionStatements[i];
break;
}
}
if (returnStatement == undefined ||
returnStatement.expression == undefined ||
!ts.isIdentifier(returnStatement.expression)) {
return false;
}
if (functionExpression.parameters.length === 0) {
// potential non-extended class or wrapped es2015 class
return ((ts.isFunctionDeclaration(firstStatement) || ts.isClassDeclaration(firstStatement)) &&
firstStatement.name !== undefined &&
returnStatement.expression.text === firstStatement.name.text);
}
else if (functionExpression.parameters.length !== 1) {
return false;
}
// Potential extended class
const functionParameter = functionExpression.parameters[0];
if (!ts.isIdentifier(functionParameter.name) ||
functionParameter.name.text !== superParameterName) {
return false;
}
if (functionStatements.length < 3 || !ts.isExpressionStatement(firstStatement)) {
return false;
}
if (!ts.isCallExpression(firstStatement.expression)) {
return false;
}
const extendCallExpression = firstStatement.expression;
let functionName;
if (ts.isIdentifier(extendCallExpression.expression)) {
functionName = extendCallExpression.expression.text;
}
else if (ts.isPropertyAccessExpression(extendCallExpression.expression)) {
functionName = extendCallExpression.expression.name.text;
}
if (!functionName || !functionName.endsWith(extendsHelperName)) {
return false;
}
if (extendCallExpression.arguments.length === 0) {
return false;
}
const lastArgument = extendCallExpression.arguments[extendCallExpression.arguments.length - 1];
if (!ts.isIdentifier(lastArgument) || lastArgument.text !== functionParameter.name.text) {
return false;
}
const secondStatement = functionStatements[1];
return (ts.isFunctionDeclaration(secondStatement) &&
secondStatement.name !== undefined &&
returnStatement.expression.text === secondStatement.name.text);
}