improve regex for completion-returning steps

tc39 · Nov 1, 2023 · c4106c1 · c4106c1
1 parent 11affd1
commit c4106c1
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Showing 2 changed files with 66 additions and 3 deletions.
diff --git a/src/Algorithm.ts b/src/Algorithm.ts
@@ -87,7 +87,7 @@ export default class Algorithm extends Builder {
                 continue;
               }
               const completionyThing = part.contents.match(
-                /\b(ReturnIfAbrupt|throw|Return (Normal|Throw)?Completion|the result of evaluating)\b|(?<=[\s(])\?\s/i
+                /\b(ReturnIfAbrupt|(^|(?<=, ))[tT]hrow a|[rR]eturn (Normal|Throw|Return)?Completion\(|[rR]eturn( a| a new| the)? Completion Record|the result of evaluating)(\b|$)|(?<=[\s(])\?\s/
               );
               if (completionyThing != null) {
                 if (returnType?.kind === 'completion') {

diff --git a/test/typecheck.js b/test/typecheck.js
@@ -254,7 +254,28 @@ describe('typechecking completions', () => {
         <dl class="header">
         </dl>
         <emu-alg>
-          1. ${M}Throw a new TypeError.
+          1. ${M}Throw a *TypeError* exception.
+        </emu-alg>
+        </emu-clause>
+        `,
+        {
+          ruleId: 'completiony-thing-in-non-completion-algorithm',
+          nodeType: 'emu-alg',
+          message:
+            'this would return a Completion Record, but the containing AO is declared not to return a Completion Record',
+        }
+      );
+
+      await assertLint(
+        positioned`
+        <emu-clause id="example" type="abstract operation">
+        <h1>
+          ExampleAlg (): a Number
+        </h1>
+        <dl class="header">
+        </dl>
+        <emu-alg>
+          1. If some condition is met, ${M}throw a *TypeError* exception.
         </emu-alg>
         </emu-clause>
         `,
@@ -290,6 +311,28 @@ describe('typechecking completions', () => {
           extraBiblios: [biblio],
         }
       );
+
+      await assertLint(
+        positioned`
+        <emu-clause id="example" type="abstract operation">
+        <h1>
+          ExampleAlg (): a Number
+        </h1>
+        <dl class="header">
+        </dl>
+        <emu-alg>
+          1. Let _x_ be 0.
+          1. ${M}Return Completion Record { [[Type]]: ~return~, [[Value]]: _x_, [[Target]]: ~empty~ }.
+        </emu-alg>
+        </emu-clause>
+        `,
+        {
+          ruleId: 'completiony-thing-in-non-completion-algorithm',
+          nodeType: 'emu-alg',
+          message:
+            'this would return a Completion Record, but the containing AO is declared not to return a Completion Record',
+        }
+      );
     });
 
     it('negative', async () => {
@@ -314,6 +357,26 @@ describe('typechecking completions', () => {
           extraBiblios: [biblio],
         }
       );
+
+      await assertLintFree(
+        `
+          <emu-clause id="example" type="abstract operation">
+          <h1>
+            ExampleAlg (): a Number
+          </h1>
+          <dl class="header">
+          </dl>
+          <emu-alg>
+            1. Do something with Completion(0).
+            1. NOTE: This will not throw a *TypeError* exception.
+            1. Consider whether something is a return completion.
+          </emu-alg>
+          </emu-clause>
+        `,
+        {
+          extraBiblios: [biblio],
+        }
+      );
     });
   });
 
@@ -507,7 +570,7 @@ describe('typechecking completions', () => {
         <dl class="header">
         </dl>
         <emu-alg>
-          1. Throw something.
+          1. Throw a *TypeError* exception.
         </emu-alg>
         </emu-clause>