Don't call customizeComponentName on curly components

packages/@glimmer/integration-tests/test/compiler/compile-options-test.ts

@@ -72,6 +72,52 @@ module('[glimmer-compiler] precompile', ({ test }) => {
     assert.equal(componentName, 'rental', 'customized component name was used');
   });
 
+  test('customizeComponentName is not invoked on curly components', function (assert) {
+    let wire = JSON.parse(
+      precompile('{{#my-component}}hello{{/my-component}}', {
+        customizeComponentName(input: string) {
+          return input.toUpperCase();
+        },
+      })
+    );
+
+    let block: WireFormat.SerializedTemplateBlock = JSON.parse(wire.block);
+
+    let [[, componentNameExpr]] = block[0] as [WireFormat.Statements.Block];
+
+    glimmerAssert(
+      Array.isArray(componentNameExpr) &&
+        componentNameExpr[0] === SexpOpcodes.GetFreeAsComponentHead,
+      `component name is a free variable lookup`
+    );
+
+    let componentName = block[3][componentNameExpr[1]];
+    assert.equal(componentName, 'my-component', 'original component name was used');
+  });
+
+  test('customizeComponentName is not invoked on angle-bracket-like name invoked with curlies', function (assert) {
+    let wire = JSON.parse(
+      precompile('{{#MyComponent}}hello{{/MyComponent}}', {
+        customizeComponentName(input: string) {
+          return input.toUpperCase();
+        },
+      })
+    );
+
+    let block: WireFormat.SerializedTemplateBlock = JSON.parse(wire.block);
+
+    let [[, componentNameExpr]] = block[0] as [WireFormat.Statements.Block];
+
+    glimmerAssert(
+      Array.isArray(componentNameExpr) &&
+        componentNameExpr[0] === SexpOpcodes.GetFreeAsComponentHead,
+      `component name is a free variable lookup`
+    );
+
+    let componentName = block[3][componentNameExpr[1]];
+    assert.equal(componentName, 'MyComponent', 'original component name was used');
+  });
+
   test('lowercased names are not resolved or customized in resolution mode', (assert) => {
     let wire = JSON.parse(
       precompile('<rental />', {

packages/@glimmer/syntax/lib/symbol-table.ts

@@ -2,6 +2,7 @@ import { Core, Dict, SexpOpcodes } from '@glimmer/interfaces';
 import { dict } from '@glimmer/util';
 
 import { ASTv2 } from '..';
+import { isUpperCase } from './utils';
 
 export abstract class SymbolTable {
   static top(
@@ -86,7 +87,13 @@ export class ProgramSymbolTable extends SymbolTable {
   }
 
   allocateFree(name: string, resolution: ASTv2.FreeVarResolution): number {
-    if (resolution.resolution() === SexpOpcodes.GetFreeAsComponentHead) {
+    // If the name in question is an uppercase (i.e. angle-bracket) component invocation, run
+    // the optional `customizeComponentName` function provided to the precompiler.
+    if (
+      resolution.resolution() === SexpOpcodes.GetFreeAsComponentHead &&
+      resolution.isAngleBracket &&
+      isUpperCase(name)
+    ) {
       name = this.customizeComponentName(name);
     }
 

packages/@glimmer/syntax/lib/utils.ts

@@ -114,3 +114,11 @@ export function printLiteral(literal: ASTv1.Literal): string {
     return JSON.stringify(literal.value);
   }
 }
+
+export function isUpperCase(tag: string): boolean {
+  return tag[0] === tag[0].toUpperCase() && tag[0] !== tag[0].toLowerCase();
+}
+
+export function isLowerCase(tag: string): boolean {
+  return tag[0] === tag[0].toLowerCase() && tag[0] !== tag[0].toUpperCase();
+}

packages/@glimmer/syntax/lib/v2-a/loose-resolution.ts

@@ -39,7 +39,7 @@ export function BlockSyntaxContext(node: ASTv1.BlockStatement): ASTv2.FreeVarRes
 
 export function ComponentSyntaxContext(node: ASTv1.PathExpression): ASTv2.FreeVarResolution | null {
   if (isSimplePath(node)) {
-    return ASTv2.LooseModeResolution.namespaced(ASTv2.FreeVarNamespace.Component);
+    return ASTv2.LooseModeResolution.namespaced(ASTv2.FreeVarNamespace.Component, true);
   } else {
     return null;
   }

packages/@glimmer/syntax/lib/v2-a/normalize.ts

@@ -10,6 +10,7 @@ import { SourceSpan } from '../source/span';
 import { SpanList } from '../source/span-list';
 import { BlockSymbolTable, ProgramSymbolTable, SymbolTable } from '../symbol-table';
 import { generateSyntaxError } from '../syntax-error';
+import { isLowerCase, isUpperCase } from '../utils';
 import * as ASTv1 from '../v1/api';
 import b from '../v1/parser-builders';
 import * as ASTv2 from './api';
@@ -866,14 +867,6 @@ class ElementChildren extends Children {
   }
 }
 
-function isUpperCase(tag: string): boolean {
-  return tag[0] === tag[0].toUpperCase() && tag[0] !== tag[0].toLowerCase();
-}
-
-function isLowerCase(tag: string): boolean {
-  return tag[0] === tag[0].toLowerCase() && tag[0] !== tag[0].toUpperCase();
-}
-
 function printPath(node: ASTv1.PathExpression | ASTv1.CallNode): string {
   if (node.type !== 'PathExpression' && node.path.type === 'PathExpression') {
     return printPath(node.path);

packages/@glimmer/syntax/lib/v2-a/objects/resolution.ts

@@ -22,6 +22,8 @@ export class StrictResolution {
   serialize(): SerializedResolution {
     return 'Strict';
   }
+
+  readonly isAngleBracket = false;
 }
 
 export const STRICT_RESOLUTION = new StrictResolution();
@@ -46,11 +48,14 @@ export class LooseModeResolution {
    *
    * @see {NamespacedAmbiguity}
    */
-  static namespaced(namespace: FreeVarNamespace): LooseModeResolution {
-    return new LooseModeResolution({
-      namespaces: [namespace],
-      fallback: false,
-    });
+  static namespaced(namespace: FreeVarNamespace, isAngleBracket = false): LooseModeResolution {
+    return new LooseModeResolution(
+      {
+        namespaces: [namespace],
+        fallback: false,
+      },
+      isAngleBracket
+    );
   }
 
   /**
@@ -136,7 +141,7 @@ export class LooseModeResolution {
     return new LooseModeResolution({ namespaces: [FreeVarNamespace.Helper], fallback: true });
   }
 
-  constructor(readonly ambiguity: Ambiguity) {}
+  constructor(readonly ambiguity: Ambiguity, readonly isAngleBracket = false) {}
 
   resolution(): GetContextualFreeOp {
     if (this.ambiguity.namespaces.length === 0) {