angular-docs-cn/modules/@angular/compiler/test/expression_parser/unparser.ts

197 lines
4.9 KiB
TypeScript

import {
AST,
AstVisitor,
PropertyRead,
PropertyWrite,
Binary,
Chain,
Conditional,
EmptyExpr,
BindingPipe,
FunctionCall,
ImplicitReceiver,
Interpolation,
KeyedRead,
KeyedWrite,
LiteralArray,
LiteralMap,
LiteralPrimitive,
MethodCall,
PrefixNot,
Quote,
SafePropertyRead,
SafeMethodCall
} from '../../src/expression_parser/ast';
import {StringWrapper, isPresent, isString} from '../../src/facade/lang';
export class Unparser implements AstVisitor {
private static _quoteRegExp = /"/g;
private _expression: string;
unparse(ast: AST) {
this._expression = '';
this._visit(ast);
return this._expression;
}
visitPropertyRead(ast: PropertyRead, context: any) {
this._visit(ast.receiver);
this._expression += ast.receiver instanceof ImplicitReceiver ? `${ast.name}` : `.${ast.name}`;
}
visitPropertyWrite(ast: PropertyWrite, context: any) {
this._visit(ast.receiver);
this._expression +=
ast.receiver instanceof ImplicitReceiver ? `${ast.name} = ` : `.${ast.name} = `;
this._visit(ast.value);
}
visitBinary(ast: Binary, context: any) {
this._visit(ast.left);
this._expression += ` ${ast.operation} `;
this._visit(ast.right);
}
visitChain(ast: Chain, context: any) {
var len = ast.expressions.length;
for (let i = 0; i < len; i++) {
this._visit(ast.expressions[i]);
this._expression += i == len - 1 ? ';' : '; ';
}
}
visitConditional(ast: Conditional, context: any) {
this._visit(ast.condition);
this._expression += ' ? ';
this._visit(ast.trueExp);
this._expression += ' : ';
this._visit(ast.falseExp);
}
visitPipe(ast: BindingPipe, context: any) {
this._expression += '(';
this._visit(ast.exp);
this._expression += ` | ${ast.name}`;
ast.args.forEach(arg => {
this._expression += ':';
this._visit(arg);
});
this._expression += ')';
}
visitFunctionCall(ast: FunctionCall, context: any) {
this._visit(ast.target);
this._expression += '(';
var isFirst = true;
ast.args.forEach(arg => {
if (!isFirst) this._expression += ', ';
isFirst = false;
this._visit(arg);
});
this._expression += ')';
}
visitImplicitReceiver(ast: ImplicitReceiver, context: any) {}
visitInterpolation(ast: Interpolation, context: any) {
for (let i = 0; i < ast.strings.length; i++) {
this._expression += ast.strings[i];
if (i < ast.expressions.length) {
this._expression += '{{ ';
this._visit(ast.expressions[i]);
this._expression += ' }}';
}
}
}
visitKeyedRead(ast: KeyedRead, context: any) {
this._visit(ast.obj);
this._expression += '[';
this._visit(ast.key);
this._expression += ']';
}
visitKeyedWrite(ast: KeyedWrite, context: any) {
this._visit(ast.obj);
this._expression += '[';
this._visit(ast.key);
this._expression += '] = ';
this._visit(ast.value);
}
visitLiteralArray(ast: LiteralArray, context: any) {
this._expression += '[';
var isFirst = true;
ast.expressions.forEach(expression => {
if (!isFirst) this._expression += ', ';
isFirst = false;
this._visit(expression);
});
this._expression += ']';
}
visitLiteralMap(ast: LiteralMap, context: any) {
this._expression += '{';
var isFirst = true;
for (let i = 0; i < ast.keys.length; i++) {
if (!isFirst) this._expression += ', ';
isFirst = false;
this._expression += `${ast.keys[i]}: `;
this._visit(ast.values[i]);
}
this._expression += '}';
}
visitLiteralPrimitive(ast: LiteralPrimitive, context: any) {
if (isString(ast.value)) {
this._expression += `"${StringWrapper.replaceAll(ast.value, Unparser._quoteRegExp, '\"')}"`;
} else {
this._expression += `${ast.value}`;
}
}
visitMethodCall(ast: MethodCall, context: any) {
this._visit(ast.receiver);
this._expression += ast.receiver instanceof ImplicitReceiver ? `${ast.name}(` : `.${ast.name}(`;
var isFirst = true;
ast.args.forEach(arg => {
if (!isFirst) this._expression += ', ';
isFirst = false;
this._visit(arg);
});
this._expression += ')';
}
visitPrefixNot(ast: PrefixNot, context: any) {
this._expression += '!';
this._visit(ast.expression);
}
visitSafePropertyRead(ast: SafePropertyRead, context: any) {
this._visit(ast.receiver);
this._expression += `?.${ast.name}`;
}
visitSafeMethodCall(ast: SafeMethodCall, context: any) {
this._visit(ast.receiver);
this._expression += `?.${ast.name}(`;
var isFirst = true;
ast.args.forEach(arg => {
if (!isFirst) this._expression += ', ';
isFirst = false;
this._visit(arg);
});
this._expression += ')';
}
visitQuote(ast: Quote, context: any) {
this._expression += `${ast.prefix}:${ast.uninterpretedExpression}`;
}
private _visit(ast: AST) { ast.visit(this); }
}