1 files changed, 61 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/wasm/directiveless/bug1645310.js b/js/src/jit-test/tests/wasm/directiveless/bug1645310.js
new file mode 100644
index 0000000000..3532886c6a
--- /dev/null
+++ b/js/src/jit-test/tests/wasm/directiveless/bug1645310.js
@@ -0,0 +1,61 @@
+// |jit-test| --wasm-compiler=optimizing; skip-if: !wasmIsSupported()
+
+// In this case we're setting things up so that wasm can't be compiled, as the
+// only available compiler is Ion, and enabling the Debugger will disable Ion.
+//
+// The test tests that the lazy creation of the WebAssembly object is not
+// dependent on whether WebAssembly can be compiled or not: if wasm is supported
+// then the WebAssembly object should always be created.  The fact that wasm
+// can't be compiled is a separate matter.
+//
+// IT'S IMPORTANT NOT TO MENTION THE WEBASSEMBLY OBJECT UNTIL AFTER THE DEBUGGER
+// HAS BEEN CREATED, AND NOT TO LOAD lib/wasm.js OR OTHER WASM CODE HERE.
+
+var g7 = newGlobal({newCompartment: true});
+g7.parent = this;
+g7.eval("var dbg = Debugger(parent)");
+assertEq(typeof WebAssembly, "object");
+
+// Test that validation works even if compilers are not available.
+
+WebAssembly.validate(wasmTextToBinary('(module (func))'));
+
+// Test that compilation fails with a sensible error.
+
+var bits = wasmTextToBinary('(module (func))');
+var msg = /no WebAssembly compiler available/
+var exn;
+
+exn = null;
+try { new WebAssembly.Module(bits); } catch (e) { exn = e; }
+assertEq(Boolean(exn), true);
+assertEq(Boolean(String(exn).match(msg)), true);
+
+exn = null;
+try { WebAssembly.compile(bits); } catch (e) { exn = e; }
+assertEq(Boolean(exn), true);
+assertEq(Boolean(String(exn).match(msg)), true);
+
+exn = null;
+try { WebAssembly.instantiate(bits); } catch (e) { exn = e; }
+assertEq(Boolean(exn), true);
+assertEq(Boolean(String(exn).match(msg)), true);
+
+// We do not use wasmStreamingEnabled() here because that checks whether
+// compilers are available, and that is precisely what we want to be checking
+// ourselves.  But streaming compilation is available only if there are helper
+// threads, so that's an OK proxy.
+
+if (helperThreadCount() > 0) {
+    exn = null;
+    WebAssembly.compileStreaming(bits).catch(e => { exn = e; });
+    drainJobQueue();
+    assertEq(Boolean(exn), true);
+    assertEq(Boolean(String(exn).match(msg)), true);
+
+    exn = null;
+    WebAssembly.instantiateStreaming(bits).catch(e => { exn = e; });
+    drainJobQueue();
+    assertEq(Boolean(exn), true);
+    assertEq(Boolean(String(exn).match(msg)), true);
+}