fix(compiler): correct the `KeySpan` for animation events and properties (#40347)

We should provide the completion when the cursor is in the attribute
name after the `@` and `animate-`, but now the `KeySpan` starts from the
`@` or `animate-`. For example, the animation event `(@name.done)="v"`,
we can know where the cursor is by the `KeySpan` of `name.done` exactly,
it's in the event name or in the phase name.

PR Close #40347

packages/compiler/src/template_parser/binding_parser.ts

@@ -244,6 +244,10 @@ export class BindingParser {
       targetProps: ParsedProperty[], keySpan?: ParseSourceSpan) {
     if (isAnimationLabel(name)) {
       name = name.substring(1);
+      if (keySpan !== undefined) {
+        keySpan = moveParseSourceSpan(
+            keySpan, new AbsoluteSourceSpan(keySpan.start.offset + 1, keySpan.end.offset));
+      }
       if (value) {
         this._reportError(
             `Assigning animation triggers via @prop="exp" attributes with an expression is invalid.` +
@@ -274,9 +278,19 @@ export class BindingParser {
     if (name.startsWith(ANIMATE_PROP_PREFIX)) {
       isAnimationProp = true;
       name = name.substring(ANIMATE_PROP_PREFIX.length);
+      if (keySpan !== undefined) {
+        keySpan = moveParseSourceSpan(
+            keySpan,
+            new AbsoluteSourceSpan(
+                keySpan.start.offset + ANIMATE_PROP_PREFIX.length, keySpan.end.offset));
+      }
     } else if (isAnimationLabel(name)) {
       isAnimationProp = true;
       name = name.substring(1);
+      if (keySpan !== undefined) {
+        keySpan = moveParseSourceSpan(
+            keySpan, new AbsoluteSourceSpan(keySpan.start.offset + 1, keySpan.end.offset));
+      }
     }
 
     if (isAnimationProp) {
@@ -424,6 +438,10 @@ export class BindingParser {
 
     if (isAnimationLabel(name)) {
       name = name.substr(1);
+      if (keySpan !== undefined) {
+        keySpan = moveParseSourceSpan(
+            keySpan, new AbsoluteSourceSpan(keySpan.start.offset + 1, keySpan.end.offset));
+      }
       this._parseAnimationEvent(name, expression, sourceSpan, handlerSpan, targetEvents, keySpan);
     } else {
       this._parseRegularEvent(

packages/compiler/test/render3/r3_ast_spans_spec.ts

@@ -193,6 +193,30 @@ describe('R3 AST source spans', () => {
         ['BoundAttribute', 'data-prop="{{v}}"', 'prop', '{{v}}'],
       ]);
     });
+
+    it('is correct for bound properties via @', () => {
+      expectFromHtml('<div bind-@animation="v"></div>').toEqual([
+        ['Element', '<div bind-@animation="v"></div>', '<div bind-@animation="v">', '</div>'],
+        ['BoundAttribute', 'bind-@animation="v"', 'animation', 'v'],
+      ]);
+    });
+
+    it('is correct for bound properties via animation-', () => {
+      expectFromHtml('<div bind-animate-animationName="v"></div>').toEqual([
+        [
+          'Element', '<div bind-animate-animationName="v"></div>',
+          '<div bind-animate-animationName="v">', '</div>'
+        ],
+        ['BoundAttribute', 'bind-animate-animationName="v"', 'animationName', 'v'],
+      ]);
+    });
+
+    it('is correct for bound properties via @ without value', () => {
+      expectFromHtml('<div @animation></div>').toEqual([
+        ['Element', '<div @animation></div>', '<div @animation>', '</div>'],
+        ['BoundAttribute', '@animation', 'animation', '<empty>'],
+      ]);
+    });
   });
 
   describe('templates', () => {
@@ -401,6 +425,13 @@ describe('R3 AST source spans', () => {
         ['BoundEvent', 'data-bindon-prop="v"', 'prop', 'v'],
       ]);
     });
+
+    it('is correct for bound events via @', () => {
+      expectFromHtml('<div (@name.done)="v"></div>').toEqual([
+        ['Element', '<div (@name.done)="v"></div>', '<div (@name.done)="v">', '</div>'],
+        ['BoundEvent', '(@name.done)="v"', 'name.done', 'v'],
+      ]);
+    });
   });
 
   describe('references', () => {