angular-cn/packages/language-service/src/completions.ts

587 lines
20 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 {AST, AstPath, Attribute, BoundDirectivePropertyAst, BoundElementPropertyAst, BoundEventAst, BoundTextAst, CssSelector, Element, ElementAst, ImplicitReceiver, NAMED_ENTITIES, Node as HtmlAst, NullTemplateVisitor, ParseSpan, PropertyRead, TagContentType, TemplateBinding, Text, findNode, getHtmlTagDefinition} from '@angular/compiler';
import {$$, $_, isAsciiLetter, isDigit} from '@angular/compiler/src/chars';
import {AstResult} from './common';
import {getExpressionScope} from './expression_diagnostics';
import {getExpressionCompletions} from './expressions';
import {attributeNames, elementNames, eventNames, propertyNames} from './html_info';
import {InlineTemplate} from './template';
import * as ng from './types';
import {diagnosticInfoFromTemplateInfo, findTemplateAstAt, getSelectors, hasTemplateReference, inSpan, spanOf} from './utils';
const HIDDEN_HTML_ELEMENTS: ReadonlySet<string> =
new Set(['html', 'script', 'noscript', 'base', 'body', 'title', 'head', 'link']);
const HTML_ELEMENTS: ReadonlyArray<ng.CompletionEntry> =
elementNames().filter(name => !HIDDEN_HTML_ELEMENTS.has(name)).map(name => {
return {
name,
kind: ng.CompletionKind.HTML_ELEMENT,
sortText: name,
};
});
const ANGULAR_ELEMENTS: ReadonlyArray<ng.CompletionEntry> = [
{
name: 'ng-container',
kind: ng.CompletionKind.ANGULAR_ELEMENT,
sortText: 'ng-container',
},
{
name: 'ng-content',
kind: ng.CompletionKind.ANGULAR_ELEMENT,
sortText: 'ng-content',
},
{
name: 'ng-template',
kind: ng.CompletionKind.ANGULAR_ELEMENT,
sortText: 'ng-template',
},
];
function isIdentifierPart(code: number) {
// Identifiers consist of alphanumeric characters, '_', or '$'.
return isAsciiLetter(code) || isDigit(code) || code == $$ || code == $_;
}
/**
* Gets the span of word in a template that surrounds `position`. If there is no word around
* `position`, nothing is returned.
*/
function getBoundedWordSpan(templateInfo: AstResult, position: number): ts.TextSpan|undefined {
const {template} = templateInfo;
const templateSrc = template.source;
if (!templateSrc) return;
// TODO(ayazhafiz): A solution based on word expansion will always be expensive compared to one
// based on ASTs. Whatever penalty we incur is probably manageable for small-length (i.e. the
// majority of) identifiers, but the current solution involes a number of branchings and we can't
// control potentially very long identifiers. Consider moving to an AST-based solution once
// existing difficulties with AST spans are more clearly resolved (see #31898 for discussion of
// known problems, and #33091 for how they affect text replacement).
//
// `templatePosition` represents the right-bound location of a cursor in the template.
// key.ent|ry
// ^---- cursor, at position `r` is at.
// A cursor is not itself a character in the template; it has a left (lower) and right (upper)
// index bound that hugs the cursor itself.
let templatePosition = position - template.span.start;
// To perform word expansion, we want to determine the left and right indices that hug the cursor.
// There are three cases here.
let left, right;
if (templatePosition === 0) {
// 1. Case like
// |rest of template
// the cursor is at the start of the template, hugged only by the right side (0-index).
left = right = 0;
} else if (templatePosition === templateSrc.length) {
// 2. Case like
// rest of template|
// the cursor is at the end of the template, hugged only by the left side (last-index).
left = right = templateSrc.length - 1;
} else {
// 3. Case like
// wo|rd
// there is a clear left and right index.
left = templatePosition - 1;
right = templatePosition;
}
if (!isIdentifierPart(templateSrc.charCodeAt(left)) &&
!isIdentifierPart(templateSrc.charCodeAt(right))) {
// Case like
// .|.
// left ---^ ^--- right
// There is no word here.
return;
}
// Expand on the left and right side until a word boundary is hit. Back up one expansion on both
// side to stay inside the word.
while (left >= 0 && isIdentifierPart(templateSrc.charCodeAt(left))) --left;
++left;
while (right < templateSrc.length && isIdentifierPart(templateSrc.charCodeAt(right))) ++right;
--right;
const absoluteStartPosition = position - (templatePosition - left);
const length = right - left + 1;
return {start: absoluteStartPosition, length};
}
export function getTemplateCompletions(
templateInfo: AstResult, position: number): ng.CompletionEntry[] {
let result: ng.CompletionEntry[] = [];
const {htmlAst, template} = templateInfo;
// The templateNode starts at the delimiter character so we add 1 to skip it.
const templatePosition = position - template.span.start;
const path = findNode(htmlAst, templatePosition);
const mostSpecific = path.tail;
if (path.empty || !mostSpecific) {
result = elementCompletions(templateInfo);
} else {
const astPosition = templatePosition - mostSpecific.sourceSpan.start.offset;
mostSpecific.visit(
{
visitElement(ast) {
const startTagSpan = spanOf(ast.sourceSpan);
const tagLen = ast.name.length;
// + 1 for the opening angle bracket
if (templatePosition <= startTagSpan.start + tagLen + 1) {
// If we are in the tag then return the element completions.
result = elementCompletions(templateInfo);
} else if (templatePosition < startTagSpan.end) {
// We are in the attribute section of the element (but not in an attribute).
// Return the attribute completions.
result = attributeCompletions(templateInfo, path);
}
},
visitAttribute(ast) {
if (!ast.valueSpan || !inSpan(templatePosition, spanOf(ast.valueSpan))) {
// We are in the name of an attribute. Show attribute completions.
result = attributeCompletions(templateInfo, path);
} else if (ast.valueSpan && inSpan(templatePosition, spanOf(ast.valueSpan))) {
result = attributeValueCompletions(templateInfo, templatePosition, ast);
}
},
visitText(ast) {
// Check if we are in a entity.
result = entityCompletions(getSourceText(template, spanOf(ast)), astPosition);
if (result.length) return result;
result = interpolationCompletions(templateInfo, templatePosition);
if (result.length) return result;
const element = path.first(Element);
if (element) {
const definition = getHtmlTagDefinition(element.name);
if (definition.contentType === TagContentType.PARSABLE_DATA) {
result = voidElementAttributeCompletions(templateInfo, path);
if (!result.length) {
// If the element can hold content, show element completions.
result = elementCompletions(templateInfo);
}
}
} else {
// If no element container, implies parsable data so show elements.
result = voidElementAttributeCompletions(templateInfo, path);
if (!result.length) {
result = elementCompletions(templateInfo);
}
}
},
visitComment(ast) {},
visitExpansion(ast) {},
visitExpansionCase(ast) {}
},
null);
}
const replacementSpan = getBoundedWordSpan(templateInfo, position);
return result.map(entry => {
return {
...entry, replacementSpan,
};
});
}
function attributeCompletions(info: AstResult, path: AstPath<HtmlAst>): ng.CompletionEntry[] {
const item = path.tail instanceof Element ? path.tail : path.parentOf(path.tail);
if (item instanceof Element) {
return attributeCompletionsForElement(info, item.name);
}
return [];
}
function attributeCompletionsForElement(
info: AstResult, elementName: string): ng.CompletionEntry[] {
const results: ng.CompletionEntry[] = [];
if (info.template instanceof InlineTemplate) {
// Provide HTML attributes completion only for inline templates
for (const name of attributeNames(elementName)) {
results.push({
name,
kind: ng.CompletionKind.HTML_ATTRIBUTE,
sortText: name,
});
}
}
// Add html properties
for (const name of propertyNames(elementName)) {
results.push({
name: `[${name}]`,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
}
// Add html events
for (const name of eventNames(elementName)) {
results.push({
name: `(${name})`,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
}
// Add Angular attributes
results.push(...angularAttributes(info, elementName));
return results;
}
function attributeValueCompletions(
info: AstResult, position: number, attr: Attribute): ng.CompletionEntry[] {
const path = findTemplateAstAt(info.templateAst, position);
if (!path.tail) {
return [];
}
const dinfo = diagnosticInfoFromTemplateInfo(info);
const visitor =
new ExpressionVisitor(info, position, () => getExpressionScope(dinfo, path, false), attr);
path.tail.visit(visitor, null);
const {results} = visitor;
if (results.length) {
return results;
}
// Try allowing widening the path
const widerPath = findTemplateAstAt(info.templateAst, position, /* allowWidening */ true);
if (widerPath.tail) {
const widerVisitor = new ExpressionVisitor(
info, position, () => getExpressionScope(dinfo, widerPath, false), attr);
widerPath.tail.visit(widerVisitor, null);
return widerVisitor.results;
}
return results;
}
function elementCompletions(info: AstResult): ng.CompletionEntry[] {
const results: ng.CompletionEntry[] = [...ANGULAR_ELEMENTS];
if (info.template instanceof InlineTemplate) {
// Provide HTML elements completion only for inline templates
results.push(...HTML_ELEMENTS);
}
// Collect the elements referenced by the selectors
const components = new Set<string>();
for (const selector of getSelectors(info).selectors) {
const name = selector.element;
if (name && !components.has(name)) {
components.add(name);
results.push({
name,
kind: ng.CompletionKind.COMPONENT,
sortText: name,
});
}
}
return results;
}
function entityCompletions(value: string, position: number): ng.CompletionEntry[] {
// Look for entity completions
const re = /&[A-Za-z]*;?(?!\d)/g;
let found: RegExpExecArray|null;
let result: ng.CompletionEntry[] = [];
while (found = re.exec(value)) {
let len = found[0].length;
if (position >= found.index && position < (found.index + len)) {
result = Object.keys(NAMED_ENTITIES).map(name => {
return {
name: `&${name};`,
kind: ng.CompletionKind.ENTITY,
sortText: name,
};
});
break;
}
}
return result;
}
function interpolationCompletions(info: AstResult, position: number): ng.CompletionEntry[] {
// Look for an interpolation in at the position.
const templatePath = findTemplateAstAt(info.templateAst, position);
if (!templatePath.tail) {
return [];
}
const visitor = new ExpressionVisitor(
info, position,
() => getExpressionScope(diagnosticInfoFromTemplateInfo(info), templatePath, false));
templatePath.tail.visit(visitor, null);
return visitor.results;
}
// There is a special case of HTML where text that contains a unclosed tag is treated as
// text. For exaple '<h1> Some <a text </h1>' produces a text nodes inside of the H1
// element "Some <a text". We, however, want to treat this as if the user was requesting
// the attributes of an "a" element, not requesting completion in the a text element. This
// code checks for this case and returns element completions if it is detected or undefined
// if it is not.
function voidElementAttributeCompletions(
info: AstResult, path: AstPath<HtmlAst>): ng.CompletionEntry[] {
const tail = path.tail;
if (tail instanceof Text) {
const match = tail.value.match(/<(\w(\w|\d|-)*:)?(\w(\w|\d|-)*)\s/);
// The position must be after the match, otherwise we are still in a place where elements
// are expected (such as `<|a` or `<a|`; we only want attributes for `<a |` or after).
if (match &&
path.position >= (match.index || 0) + match[0].length + tail.sourceSpan.start.offset) {
return attributeCompletionsForElement(info, match[3]);
}
}
return [];
}
class ExpressionVisitor extends NullTemplateVisitor {
private readonly completions = new Map<string, ng.CompletionEntry>();
constructor(
private readonly info: AstResult, private readonly position: number,
private readonly getExpressionScope: () => ng.SymbolTable,
private readonly attr?: Attribute) {
super();
}
get results(): ng.CompletionEntry[] { return Array.from(this.completions.values()); }
visitDirectiveProperty(ast: BoundDirectivePropertyAst): void {
this.addAttributeValuesToCompletions(ast.value);
}
visitElementProperty(ast: BoundElementPropertyAst): void {
this.addAttributeValuesToCompletions(ast.value);
}
visitEvent(ast: BoundEventAst): void { this.addAttributeValuesToCompletions(ast.handler); }
visitElement(ast: ElementAst): void {
if (!this.attr || !this.attr.valueSpan) {
return;
}
// The attribute value is a template expression but the expression AST
// was not produced when the TemplateAst was produced so do that here.
const {templateBindings} = this.info.expressionParser.parseTemplateBindings(
this.attr.name, this.attr.value, this.attr.sourceSpan.toString(),
this.attr.sourceSpan.start.offset);
// Find where the cursor is relative to the start of the attribute value.
const valueRelativePosition = this.position - this.attr.valueSpan.start.offset;
// Find the template binding that contains the position
const binding = templateBindings.find(b => inSpan(valueRelativePosition, b.span));
if (!binding) {
return;
}
if (this.attr.name.startsWith('*')) {
this.microSyntaxInAttributeValue(this.attr, binding);
} else if (valueRelativePosition >= 0) {
// If the position is in the expression or after the key or there is no key,
// return the expression completions
const span = new ParseSpan(0, this.attr.value.length);
const offset = ast.sourceSpan.start.offset;
const receiver = new ImplicitReceiver(span, span.toAbsolute(offset));
const expressionAst = new PropertyRead(span, span.toAbsolute(offset), receiver, '');
this.addAttributeValuesToCompletions(expressionAst, valueRelativePosition);
}
}
visitBoundText(ast: BoundTextAst) {
if (inSpan(this.position, ast.value.sourceSpan)) {
const completions = getExpressionCompletions(
this.getExpressionScope(), ast.value, this.position, this.info.template.query);
if (completions) {
this.addSymbolsToCompletions(completions);
}
}
}
private addAttributeValuesToCompletions(value: AST, position?: number) {
const symbols = getExpressionCompletions(
this.getExpressionScope(), value,
position === undefined ? this.attributeValuePosition : position, this.info.template.query);
if (symbols) {
this.addSymbolsToCompletions(symbols);
}
}
private addKeysToCompletions(selector: CssSelector, key: string) {
if (key !== 'ngFor') {
return;
}
this.completions.set('let', {
name: 'let',
kind: ng.CompletionKind.KEY,
sortText: 'let',
});
if (selector.attrs.some(attr => attr === 'ngForOf')) {
this.completions.set('of', {
name: 'of',
kind: ng.CompletionKind.KEY,
sortText: 'of',
});
}
}
private addSymbolsToCompletions(symbols: ng.Symbol[]) {
for (const s of symbols) {
if (s.name.startsWith('__') || !s.public || this.completions.has(s.name)) {
continue;
}
this.completions.set(s.name, {
name: s.name,
kind: s.kind as ng.CompletionKind,
sortText: s.name,
insertText: s.callable ? `${s.name}()` : s.name,
});
}
}
private get attributeValuePosition() {
if (this.attr && this.attr.valueSpan) {
return this.position;
}
return 0;
}
/**
* This method handles the completions of attribute values for directives that
* support the microsyntax format. Examples are *ngFor and *ngIf.
* These directives allows declaration of "let" variables, adds context-specific
* symbols like $implicit, index, count, among other behaviors.
* For a complete description of such format, see
* https://angular.io/guide/structural-directives#the-asterisk--prefix
*
* @param attr descriptor for attribute name and value pair
* @param binding template binding for the expression in the attribute
*/
private microSyntaxInAttributeValue(attr: Attribute, binding: TemplateBinding) {
const key = attr.name.substring(1); // remove leading asterisk
// Find the selector - eg ngFor, ngIf, etc
const selectorInfo = getSelectors(this.info);
const selector = selectorInfo.selectors.find(s => {
// attributes are listed in (attribute, value) pairs
for (let i = 0; i < s.attrs.length; i += 2) {
if (s.attrs[i] === key) {
return true;
}
}
});
if (!selector) {
return;
}
const valueRelativePosition = this.position - attr.valueSpan !.start.offset;
if (binding.keyIsVar) {
const equalLocation = attr.value.indexOf('=');
if (equalLocation >= 0 && valueRelativePosition >= equalLocation) {
// We are after the '=' in a let clause. The valid values here are the members of the
// template reference's type parameter.
const directiveMetadata = selectorInfo.map.get(selector);
if (directiveMetadata) {
const contextTable =
this.info.template.query.getTemplateContext(directiveMetadata.type.reference);
if (contextTable) {
// This adds symbols like $implicit, index, count, etc.
this.addSymbolsToCompletions(contextTable.values());
return;
}
}
}
}
if (binding.expression && inSpan(valueRelativePosition, binding.expression.ast.span)) {
this.addAttributeValuesToCompletions(binding.expression.ast, this.position);
return;
}
this.addKeysToCompletions(selector, key);
}
}
function getSourceText(template: ng.TemplateSource, span: ng.Span): string {
return template.source.substring(span.start, span.end);
}
function angularAttributes(info: AstResult, elementName: string): ng.CompletionEntry[] {
const {selectors, map: selectorMap} = getSelectors(info);
const templateRefs = new Set<string>();
const inputs = new Set<string>();
const outputs = new Set<string>();
const others = new Set<string>();
for (const selector of selectors) {
if (selector.element && selector.element !== elementName) {
continue;
}
const summary = selectorMap.get(selector) !;
for (const attr of selector.attrs) {
if (attr) {
if (hasTemplateReference(summary.type)) {
templateRefs.add(attr);
} else {
others.add(attr);
}
}
}
for (const input of Object.values(summary.inputs)) {
inputs.add(input);
}
for (const output of Object.values(summary.outputs)) {
outputs.add(output);
}
}
const results: ng.CompletionEntry[] = [];
for (const name of templateRefs) {
results.push({
name: `*${name}`,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
}
for (const name of inputs) {
results.push({
name: `[${name}]`,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
// Add banana-in-a-box syntax
// https://angular.io/guide/template-syntax#two-way-binding-
if (outputs.has(`${name}Change`)) {
results.push({
name: `[(${name})]`,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
}
}
for (const name of outputs) {
results.push({
name: `(${name})`,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
}
for (const name of others) {
results.push({
name,
kind: ng.CompletionKind.ATTRIBUTE,
sortText: name,
});
}
return results;
}