feature: @putout/processor-wasm: apply-nesting (xtuc/webassemblyjs#1208)

Author: coderaiser

packages/processor-wasm/README.md

@@ -51,6 +51,26 @@ npm i @putout/processor-wasm -D
 +local.set $a
 ```
 
+### apply-nesting
+
+#### ❌ Example of incorrect code
+
+```wast
+(func (param $a i32) (param $b i32)
+    (get_local $a)
+    (get_local $b)
+    (i32.add)
+)
+```
+
+#### ✅ Example of correct code
+
+```wast
+(func (param $a i32) (param $b i32)
+    (i32.add (get_local $a) (get_local $b))
+)
+```
+
 ## License
 
 MIT

packages/processor-wasm/lib/lint.js

@@ -2,9 +2,12 @@ import tryCatch from 'try-catch';
 import {traverse} from '@webassemblyjs/ast';
 import {parse} from '@webassemblyjs/wast-parser';
 import {print} from '@webassemblyjs/wast-printer';
-import {rules} from './rules/index.js';
 
-export const lint = (source, {fix = true} = {}) => {
+const {entries} = Object;
+const {isArray} = Array;
+
+export const lint = (source, overrides = {}) => {
+    const {fix = true, plugins} = overrides;
     const [error, ast] = tryCatch(parse, source);
 
     if (error)
@@ -16,7 +19,7 @@ export const lint = (source, {fix = true} = {}) => {
 
     const allPlaces = [];
 
-    for (const [rule, plugin] of rules) {
+    for (const [rule, plugin] of parsePlugins(plugins)) {
         const places = [];
         const push = places.push.bind(places);
 
@@ -43,6 +46,21 @@ export const lint = (source, {fix = true} = {}) => {
     };
 };
 
+function parsePlugins(plugins) {
+    const result = [];
+    
+    for (const plugin of plugins) {
+        if (isArray(plugin)) {
+            result.push(plugin);
+            continue;
+        }
+        
+        result.push(...entries(plugin));
+    }
+    
+    return result;
+}
+
 const parseError = ({message}) => ({
     rule: 'wasm-parser-error (wasm)',
     message,

packages/processor-wasm/lib/rules/apply-nesting/fixture/apply-nesting-fix.wast

@@ -0,0 +1,10 @@
+(module
+  ;; this is simple function that adds a couple of parameters
+
+  (func (param $a i32) (param $b i32)
+    (i32.add (get.local $a) (get.local $b))
+  )
+  ;; this statement exports the function to the host environment
+
+  (export "add" (func $add))
+)

packages/processor-wasm/lib/rules/apply-nesting/fixture/apply-nesting.wast

@@ -0,0 +1,10 @@
+(module
+  ;; this is simple function that adds a couple of parameters
+  (func (param $a i32) (param $b i32)
+    (get.local $a)
+    (get.local $b)
+    (i32.add)
+  )
+  ;; this statement exports the function to the host environment
+  (export "add" (func $add))
+)

packages/processor-wasm/lib/rules/apply-nesting/fixture/nested.wast

@@ -0,0 +1,10 @@
+(module
+  ;; this is simple function that adds a couple of parameters
+
+  (func (param $a i32) (param $b i32)
+    (i32.add (get.local $a) (get.local $b))
+  )
+  ;; this statement exports the function to the host environment
+
+  (export "add" (func $add))
+)

packages/processor-wasm/lib/rules/apply-nesting/index.js

@@ -0,0 +1,24 @@
+export const report = (path) => {
+    const {id, object} = path.node;
+    return `Apply nesting for '${object}.${id}'`;
+};
+
+export const fix = (path) => {
+    const {parentPath, parentKey} = path;
+    const body = parentPath.node[parentKey];
+    const index = body.indexOf(path.node);
+    const first = body[index - 2];
+    const second = body[index - 1];
+    
+    path.node.args = [first, second];
+    body.splice(index - 2, 2);
+};
+
+export const traverse = ({push}) => ({
+    Instr(path) {
+        const {id, args} = path.node;
+        
+        if (id === 'add' && !args.length)
+            push(path);
+    },
+});

packages/processor-wasm/lib/rules/apply-nesting/index.spec.js

@@ -0,0 +1,23 @@
+import {createTest} from '#test';
+import * as plugin from './index.js';
+
+const test = createTest(import.meta.url, {
+    plugins: [
+        ['apply-nesting', plugin],
+    ],
+});
+
+test('putout: processor-wasm: apply-nesting: report', (t) => {
+    t.report('apply-nesting', `Apply nesting for 'i32.add'`);
+    t.end();
+});
+
+test('putout: processor-wasm: apply-nesting: transform', (t) => {
+    t.transform('apply-nesting');
+    t.end();
+});
+
+test('putout: processor-wasm: apply-nesting: no report: nested', (t) => {
+    t.noReport('nested');
+    t.end();
+});

packages/processor-wasm/lib/rules/index.js

@@ -1,7 +1,9 @@
 import * as convertGetLocalToLocalGet from './convert-get-local-to-local-get/index.js';
 import * as convertSetLocalToLocalSet from './convert-set-local-to-local-set/index.js';
+import * as applyNesting from './apply-nesting/index.js';
 
 export const rules = [
     ['convert-get-local-to-local-get', convertGetLocalToLocalGet],
     ['convert-set-local-to-local-set', convertSetLocalToLocalSet],
+    ['apply-nesting', applyNesting],
 ];

packages/processor-wasm/lib/wasm.js

@@ -1,4 +1,5 @@
 import {lint} from './lint.js';
+import {rules as plugins} from './rules/index.js';
 
 export const files = [
     '*.wat',
@@ -8,6 +9,7 @@ export const files = [
 export const find = (source) => {
     const result = lint(source, {
         fix: false,
+        plugins,
     });
 
     return result.places;
@@ -16,6 +18,7 @@ export const find = (source) => {
 export const fix = (source) => {
     const {code} = lint(source, {
         fix: true,
+        plugins,
     });
 
     return code;

packages/processor-wasm/package.json

@@ -49,7 +49,8 @@
     "eslint-plugin-putout": "^26.0.0",
     "madrun": "^11.0.0",
     "nodemon": "^3.0.1",
-    "putout": "*"
+    "putout": "*",
+    "supertape": "^11.1.0"
   },
   "imports": {
     "#test": {