fix(metering): properly transform try/catch/finally

Agoric · Mar 2, 2020 · 6fd28ae · 6fd28ae
1 parent a42cfec
commit 6fd28ae
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Showing 4 changed files with 81 additions and 14 deletions.
diff --git a/packages/transform-metering/src/transform.js b/packages/transform-metering/src/transform.js
@@ -132,14 +132,15 @@ const ${reid}=RegExp(${JSON.stringify(pattern)},${JSON.stringify(flags)});`);
         path.node.body = wrapWithComputeMeter(blockify(path.node.body));
       },
       // To prevent interception after exhaustion, wrap catch and finally.
+      CatchClause(path) {
+        path.node.body = wrapWithComputeMeter(path.node.body);
+      },
       TryStatement(path) {
-        if (path.node.handler) {
-          path.node.handler.body = wrapWithComputeMeter(path.node.handler.body);
+        if (path.node.handler && !t.isCatchClause(path.node.handler)) {
+          path.node.handler = wrapWithComputeMeter(path.node.handler);
         }
         if (path.node.finalizer && !path.node.finalizer[METER_GENERATED]) {
-          path.node.finalizer.body = wrapWithComputeMeter(
-            path.node.finalizer.body,
-          );
+          path.node.finalizer = wrapWithComputeMeter(path.node.finalizer);
         }
       },
       // Function definitions need a stack meter, too.

diff --git a/packages/transform-metering/test/test-transform.js b/packages/transform-metering/test/test-transform.js
@@ -42,15 +42,14 @@ test('meter transform', async t => {
         `${base}/${testDir}/source.js`,
         'utf8',
       );
-      const rewritten = await fs.promises.readFile(
-        `${base}/${testDir}/rewrite.js`,
-        'utf8',
-      );
-      t.equals(
-        rewrite(src.trimRight(), testDir),
-        rewritten.trimRight(),
-        `rewrite ${testDir}`,
-      );
+      const rewritten = await fs.promises
+        .readFile(`${base}/${testDir}/rewrite.js`, 'utf8')
+        .catch(_ => undefined);
+      const transformed = rewrite(src.trimRight(), testDir);
+      if (rewritten === undefined) {
+        console.log(transformed);
+      }
+      t.equals(transformed, rewritten.trimRight(), `rewrite ${testDir}`);
     }
   } catch (e) {
     t.isNot(e, e, 'unexpected exception');

diff --git a/packages/transform-metering/testdata/try-blocks/rewrite.js b/packages/transform-metering/testdata/try-blocks/rewrite.js
@@ -0,0 +1,34 @@
+const $m=getMeter();$m&&$m.e();try{try {
+  doit();
+} catch (e) {$m && $m.c();
+  foo(e);
+}
+
+try {
+  doit();
+} finally {$m && $m.c();
+  bar();
+}
+
+try {
+  doit();
+} catch {$m && $m.c();
+  bar();
+}
+
+try {
+  doit();
+} catch (e) {$m && $m.c();
+  foo(e);
+} finally {$m && $m.c();
+  bar();
+}
+
+try {
+  doit();
+} catch {$m && $m.c();
+  foo();
+} finally {$m && $m.c();
+  bar();
+}
+}finally{$m && $m.l();}
diff --git a/packages/transform-metering/testdata/try-blocks/source.js b/packages/transform-metering/testdata/try-blocks/source.js
@@ -0,0 +1,33 @@
+try {
+  doit();
+} catch (e) {
+  foo(e);
+}
+
+try {
+  doit();
+} finally {
+  bar();
+}
+
+try {
+  doit();
+} catch {
+  bar();
+}
+
+try {
+  doit();
+} catch (e) {
+  foo(e);
+} finally {
+  bar();
+}
+
+try {
+  doit();
+} catch {
+  foo();
+} finally {
+  bar();
+}