add reverse mappings from value to name on enums exported from rust/wasm (#2240)

Author: Treeki

crates/cli-support/src/js/mod.rs

@@ -3068,6 +3068,7 @@ impl<'a> Context<'a> {
                 variants.push_str(&variant_docs);
             }
             variants.push_str(&format!("{}:{},", name, value));
+            variants.push_str(&format!("\"{}\":\"{}\",", value, name));
             if enum_.generate_typescript {
                 self.typescript.push_str("\n");
                 if !variant_docs.is_empty() {

tests/wasm/enums.js

@@ -5,7 +5,10 @@ exports.js_c_style_enum = () => {
     assert.strictEqual(wasm.Color.Green, 0);
     assert.strictEqual(wasm.Color.Yellow, 1);
     assert.strictEqual(wasm.Color.Red, 2);
-    assert.strictEqual(Object.keys(wasm.Color).length, 3);
+    assert.strictEqual(wasm.Color[0], 'Green');
+    assert.strictEqual(wasm.Color[1], 'Yellow');
+    assert.strictEqual(wasm.Color[2], 'Red');
+    assert.strictEqual(Object.keys(wasm.Color).length, 6);
 
     assert.strictEqual(wasm.enum_cycle(wasm.Color.Green), wasm.Color.Yellow);
 };
@@ -14,7 +17,10 @@ exports.js_c_style_enum_with_custom_values = () => {
     assert.strictEqual(wasm.ColorWithCustomValues.Green, 21);
     assert.strictEqual(wasm.ColorWithCustomValues.Yellow, 34);
     assert.strictEqual(wasm.ColorWithCustomValues.Red, 2);
-    assert.strictEqual(Object.keys(wasm.ColorWithCustomValues).length, 3);
+    assert.strictEqual(wasm.ColorWithCustomValues[21], 'Green');
+    assert.strictEqual(wasm.ColorWithCustomValues[34], 'Yellow');
+    assert.strictEqual(wasm.ColorWithCustomValues[2], 'Red');
+    assert.strictEqual(Object.keys(wasm.ColorWithCustomValues).length, 6);
 
     assert.strictEqual(wasm.enum_with_custom_values_cycle(wasm.ColorWithCustomValues.Green), wasm.ColorWithCustomValues.Yellow);
 };

tests/wasm/node.js

@@ -27,7 +27,10 @@ exports.test_works = function() {
   assert.strictEqual(wasm.Color.Green, 0);
   assert.strictEqual(wasm.Color.Yellow, 1);
   assert.strictEqual(wasm.Color.Red, 2);
-  assert.strictEqual(Object.keys(wasm.Color).length, 3);
+  assert.strictEqual(wasm.Color[0], 'Green');
+  assert.strictEqual(wasm.Color[1], 'Yellow');
+  assert.strictEqual(wasm.Color[2], 'Red');
+  assert.strictEqual(Object.keys(wasm.Color).length, 6);
   assert.strictEqual(wasm.cycle(wasm.Color.Green), wasm.Color.Yellow);
 
   wasm.node_math(1.0, 2.0);