feat(compiler): support directive selectors with attributes containing `$` (#41567)

This commit adds support for `$` in when selecting attributes.

Resolves #41244.

test(language-service): Add test to expose bug caused by source file change (#41500)

This commit adds a test to expose the bug caused by source file change in
between typecheck programs.

PR Close #41500

PR Close #41567

packages/compiler/src/selector.ts

@@ -13,7 +13,7 @@ const _SELECTOR_REGEXP = new RegExp(
         '(([\\.\\#]?)[-\\w]+)|' +  // 2: "tag"; 3: "."/"#";
         // "-" should appear first in the regexp below as FF31 parses "[.-\w]" as a range
         // 4: attribute; 5: attribute_string; 6: attribute_value
-        '(?:\\[([-.\\w*]+)(?:=([\"\']?)([^\\]\"\']*)\\5)?\\])|' +  // "[name]", "[name=value]",
+        '(?:\\[([-.\\w*\\\\$]+)(?:=([\"\']?)([^\\]\"\']*)\\5)?\\])|' +  // "[name]", "[name=value]",
                                                                         // "[name="value"]",
                                                                         // "[name='value']"
         '(\\))|' +                                                      // 7: ")"
@@ -94,8 +94,10 @@ export class CssSelector {
         }
       }
       const attribute = match[SelectorRegexp.ATTRIBUTE];
+
       if (attribute) {
-        current.addAttribute(attribute, match[SelectorRegexp.ATTRIBUTE_VALUE]);
+        current.addAttribute(
+            current.unescapeAttribute(attribute), match[SelectorRegexp.ATTRIBUTE_VALUE]);
       }
       if (match[SelectorRegexp.NOT_END]) {
         inNot = false;
@@ -113,6 +115,50 @@ export class CssSelector {
     return results;
   }
 
+  /**
+   * Unescape `\$` sequences from the CSS attribute selector.
+   *
+   * This is needed because `$` can have a special meaning in CSS selectors,
+   * but we might want to match an attribute that contains `$`.
+   * [MDN web link for more
+   * info](https://developer.mozilla.org/en-US/docs/Web/CSS/Attribute_selectors).
+   * @param attr the attribute to unescape.
+   * @returns the unescaped string.
+   */
+  unescapeAttribute(attr: string): string {
+    let result = '';
+    let escaping = false;
+    for (let i = 0; i < attr.length; i++) {
+      const char = attr.charAt(i);
+      if (char === '\\') {
+        escaping = true;
+        continue;
+      }
+      if (char === '$' && !escaping) {
+        throw new Error(
+            `Error in attribute selector "${attr}". ` +
+            `Unescaped "$" is not supported. Please escape with "\\$".`);
+      }
+      escaping = false;
+      result += char;
+    }
+    return result;
+  }
+
+  /**
+   * Escape `$` sequences from the CSS attribute selector.
+   *
+   * This is needed because `$` can have a special meaning in CSS selectors,
+   * with this method we are escaping `$` with `\$'.
+   * [MDN web link for more
+   * info](https://developer.mozilla.org/en-US/docs/Web/CSS/Attribute_selectors).
+   * @param attr the attribute to escape.
+   * @returns the escaped string. 
+   */
+  escapeAttribute(attr: string): string {
+    return attr.replace(/\\/g, '\\\\').replace(/\$/g, '\\$');
+  }
+
   isElementSelector(): boolean {
     return this.hasElementSelector() && this.classNames.length == 0 && this.attrs.length == 0 &&
         this.notSelectors.length === 0;
@@ -165,7 +211,7 @@ export class CssSelector {
     }
     if (this.attrs) {
       for (let i = 0; i < this.attrs.length; i += 2) {
-        const name = this.attrs[i];
+        const name = this.escapeAttribute(this.attrs[i]);
         const value = this.attrs[i + 1];
         res += `[${name}${value ? '=' + value : ''}]`;
       }

packages/compiler/test/selector/selector_spec.ts

@@ -126,6 +126,67 @@ import {el} from '@angular/platform-browser/testing/src/browser_util';
       expect(matched).toEqual([s1[0], 1]);
     });
 
+    it('should support "$" in attribute names', () => {
+      matcher.addSelectables(s1 = CssSelector.parse('[someAttr\\$]'), 1);
+
+      expect(matcher.match(getSelectorFor({attrs: [['someAttr', '']]}), selectableCollector))
+          .toEqual(false);
+      expect(matched).toEqual([]);
+      reset();
+
+      expect(matcher.match(getSelectorFor({attrs: [['someAttr$', '']]}), selectableCollector))
+          .toEqual(true);
+      expect(matched).toEqual([s1[0], 1]);
+      reset();
+
+      matcher.addSelectables(s1 = CssSelector.parse('[some\\$attr]'), 1);
+
+      expect(matcher.match(getSelectorFor({attrs: [['someattr', '']]}), selectableCollector))
+          .toEqual(false);
+      expect(matched).toEqual([]);
+
+      expect(matcher.match(getSelectorFor({attrs: [['some$attr', '']]}), selectableCollector))
+          .toEqual(true);
+      expect(matched).toEqual([s1[0], 1]);
+      reset();
+
+      matcher.addSelectables(s1 = CssSelector.parse('[\\$someAttr]'), 1);
+
+      expect(matcher.match(getSelectorFor({attrs: [['someAttr', '']]}), selectableCollector))
+          .toEqual(false);
+      expect(matched).toEqual([]);
+
+      expect(matcher.match(getSelectorFor({attrs: [['$someAttr', '']]}), selectableCollector))
+          .toEqual(true);
+      expect(matched).toEqual([s1[0], 1]);
+      reset();
+
+      matcher.addSelectables(s1 = CssSelector.parse('[some-\\$Attr]'), 1);
+      matcher.addSelectables(s2 = CssSelector.parse('[some-\\$Attr][some-\\$-attr]'), 2);
+
+      expect(matcher.match(getSelectorFor({attrs: [['some\\$Attr', '']]}), selectableCollector))
+          .toEqual(false);
+      expect(matched).toEqual([]);
+
+      expect(matcher.match(
+                 getSelectorFor({attrs: [['some-$-attr', 'someValue'], ['some-$Attr', '']]}),
+                 selectableCollector))
+          .toEqual(true);
+      expect(matched).toEqual([s1[0], 1, s2[0], 2]);
+      reset();
+
+
+      expect(matcher.match(getSelectorFor({attrs: [['someattr$', '']]}), selectableCollector))
+          .toEqual(false);
+      expect(matched).toEqual([]);
+
+      expect(matcher.match(
+                 getSelectorFor({attrs: [['some-simple-attr', '']]}), selectableCollector))
+          .toEqual(false);
+      expect(matched).toEqual([]);
+      reset();
+    });
+
     it('should select by attr name only once if the value is from the DOM', () => {
       matcher.addSelectables(s1 = CssSelector.parse('[some-decor]'), 1);
 
@@ -307,6 +368,35 @@ import {el} from '@angular/platform-browser/testing/src/browser_util';
       expect(cssSelector.toString()).toEqual('sometag');
     });
 
+    it('should detect attr names with escaped $', () => {
+      let cssSelector = CssSelector.parse('[attrname\\$]')[0];
+      expect(cssSelector.attrs).toEqual(['attrname$', '']);
+      expect(cssSelector.toString()).toEqual('[attrname\\$]');
+
+      cssSelector = CssSelector.parse('[\\$attrname]')[0];
+      expect(cssSelector.attrs).toEqual(['$attrname', '']);
+      expect(cssSelector.toString()).toEqual('[\\$attrname]');
+
+      cssSelector = CssSelector.parse('[foo\\$bar]')[0];
+      expect(cssSelector.attrs).toEqual(['foo$bar', '']);
+      expect(cssSelector.toString()).toEqual('[foo\\$bar]');
+    });
+
+    it('should error on attr names with unescaped $', () => {
+      expect(() => CssSelector.parse('[attrname$]'))
+          .toThrowError(
+              'Error in attribute selector "attrname$". Unescaped "$" is not supported. Please escape with "\\$".');
+      expect(() => CssSelector.parse('[$attrname]'))
+          .toThrowError(
+              'Error in attribute selector "$attrname". Unescaped "$" is not supported. Please escape with "\\$".');
+      expect(() => CssSelector.parse('[foo$bar]'))
+          .toThrowError(
+              'Error in attribute selector "foo$bar". Unescaped "$" is not supported. Please escape with "\\$".');
+      expect(() => CssSelector.parse('[foo\\$bar$]'))
+          .toThrowError(
+              'Error in attribute selector "foo\\$bar$". Unescaped "$" is not supported. Please escape with "\\$".');
+    });
+
     it('should detect class names', () => {
       const cssSelector = CssSelector.parse('.someClass')[0];
       expect(cssSelector.classNames).toEqual(['someclass']);