Be smarter with when to wrap in IIFE (#37)

* refactor `shouldWrapInClosure` to be more based on the owner than the contents

* handle `await` expressions

* handle JSX usage better

* clean up commented code

* update CHANGELOG

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## CHANGELOG
 
+# 2.0.4
+
+- [#37](https://github.com/planttheidea/inline-loops.macro/pull/37/files) - Smarter IIFE wrapper determination logic
+
 # 2.0.3
 
 - [#36](https://github.com/planttheidea/inline-loops.macro/pull/36) - Allow readonly collections, and fix `reduce*` method types for callback

__tests__/__fixtures__/complex/array-element/code.js

@@ -0,0 +1,5 @@
+import { map } from '../../../../src/inline-loops.macro';
+
+function getStuff(array) {
+  return [array, map(array, (v) => v * 2)];
+}

__tests__/__fixtures__/complex/array-element/output.js

@@ -0,0 +1,9 @@
+function getStuff(array) {
+  const _length = array.length;
+  const _results = Array(_length);
+  for (let _key = 0, _v; _key < _length; ++_key) {
+    _v = array[_key];
+    _results[_key] = _v * 2;
+  }
+  return [array, _results];
+}

__tests__/__fixtures__/complex/for-each-hoisted/output.js

@@ -1,15 +1,13 @@
 import { log } from './log';
 function logItems(items) {
-  (() => {
-    const _fn = (_item) => {
-      if (!this.position) {
-        return;
-      }
-      log(_item);
-    };
-    for (let _key = 0, _length = items.length, _item; _key < _length; ++_key) {
-      _item = items[_key];
-      _fn(_item, _key, items);
+  const _fn = (_item) => {
+    if (!this.position) {
+      return;
     }
-  })();
+    log(_item);
+  };
+  for (let _key = 0, _length = items.length, _item; _key < _length; ++_key) {
+    _item = items[_key];
+    _fn(_item, _key, items);
+  }
 }

__tests__/__fixtures__/complex/for-each-right-hoisted/output.js

@@ -1,15 +1,13 @@
 import { log } from './log';
 function logItems(items) {
-  (() => {
-    const _fn = (_item) => {
-      if (!this.position) {
-        return;
-      }
-      log(_item);
-    };
-    for (let _key = items.length, _item; --_key >= 0; ) {
-      _item = items[_key];
-      _fn(_item, _key, items);
+  const _fn = (_item) => {
+    if (!this.position) {
+      return;
     }
-  })();
+    log(_item);
+  };
+  for (let _key = items.length, _item; --_key >= 0; ) {
+    _item = items[_key];
+    _fn(_item, _key, items);
+  }
 }

__tests__/__fixtures__/complex/if-statement-object/code.js

@@ -0,0 +1,14 @@
+import { mapObject } from '../../../../src/inline-loops.macro';
+
+function getStuff(object, foo) {
+  if (foo === 'bar') {
+    const state = {
+      ...state,
+      foo,
+    };
+
+    return mapObject(object, (v) => v * 2);
+  }
+
+  return object;
+}

__tests__/__fixtures__/complex/if-statement-object/output.js

@@ -0,0 +1,18 @@
+function getStuff(object, foo) {
+  if (foo === 'bar') {
+    const state = {
+      ...state,
+      foo,
+    };
+    return (() => {
+      const _results = {};
+      let _v;
+      for (const _key in object) {
+        _v = object[_key];
+        _results[_key] = _v * 2;
+      }
+      return _results;
+    })();
+  }
+  return object;
+}

__tests__/__fixtures__/complex/if-statement/output.js

@@ -1,12 +1,14 @@
 function getStuff(array, foo) {
   if (foo === 'bar') {
-    const _length = array.length;
-    const _results = Array(_length);
-    for (let _key = 0, _v; _key < _length; ++_key) {
-      _v = array[_key];
-      _results[_key] = _v * 2;
-    }
-    return _results;
+    return (() => {
+      const _length = array.length;
+      const _results = Array(_length);
+      for (let _key = 0, _v; _key < _length; ++_key) {
+        _v = array[_key];
+        _results[_key] = _v * 2;
+      }
+      return _results;
+    })();
   }
   return array;
 }

__tests__/__fixtures__/complex/jsx-conditional/code.js

@@ -0,0 +1,12 @@
+import React from 'react';
+
+import { map } from '../../../../src/inline-loops.macro';
+
+function List(props) {
+  return (
+    <ul>
+      {props.items &&
+        map(props.items, (item) => <li key={item.id}>{item.value}</li>)}
+    </ul>
+  );
+}

__tests__/__fixtures__/complex/jsx-conditional/output.js

@@ -0,0 +1,23 @@
+import React from 'react';
+function List(props) {
+  return /*#__PURE__*/ React.createElement(
+    'ul',
+    null,
+    props.items &&
+      (() => {
+        const _length = props.items.length;
+        const _results = Array(_length);
+        for (let _key = 0, _item; _key < _length; ++_key) {
+          _item = props.items[_key];
+          _results[_key] = /*#__PURE__*/ React.createElement(
+            'li',
+            {
+              key: _item.id,
+            },
+            _item.value,
+          );
+        }
+        return _results;
+      })(),
+  );
+}

__tests__/__fixtures__/complex/logical-expression-nested/code.js

@@ -0,0 +1,5 @@
+import { reduce } from '../../../../src/inline-loops.macro';
+
+function getStuff(array, override) {
+  return override || reduce(array, (a, v) => a + v * 2, 0) || 1;
+}

__tests__/__fixtures__/complex/logical-expression-nested/output.js

@@ -0,0 +1,14 @@
+function getStuff(array, override) {
+  return (
+    override ||
+    (() => {
+      let _a = 0;
+      for (let _key = 0, _length = array.length, _v; _key < _length; ++_key) {
+        _v = array[_key];
+        _a = _a + _v * 2;
+      }
+      return _a;
+    })() ||
+    1
+  );
+}

__tests__/__fixtures__/complex/object-property/code.js

@@ -0,0 +1,8 @@
+import { map } from '../../../../src/inline-loops.macro';
+
+function getStuff(array) {
+  return {
+    array,
+    doubled: map(array, (v) => v * 2),
+  };
+}

__tests__/__fixtures__/complex/object-property/output.js

@@ -0,0 +1,12 @@
+function getStuff(array) {
+  const _length = array.length;
+  const _results = Array(_length);
+  for (let _key = 0, _v; _key < _length; ++_key) {
+    _v = array[_key];
+    _results[_key] = _v * 2;
+  }
+  return {
+    array,
+    doubled: _results,
+  };
+}

__tests__/__fixtures__/complex/ternary-nested/code.js

@@ -0,0 +1,5 @@
+import { reduce } from '../../../../src/inline-loops.macro';
+
+function getStuff(array, foo) {
+  return foo ? (reduce(array, (a, v) => a + v * 2, 0) ? 'stuff' : null) : null;
+}

__tests__/__fixtures__/complex/ternary-nested/output.js

@@ -0,0 +1,14 @@
+function getStuff(array, foo) {
+  return foo
+    ? (() => {
+        let _a = 0;
+        for (let _key = 0, _length = array.length, _v; _key < _length; ++_key) {
+          _v = array[_key];
+          _a = _a + _v * 2;
+        }
+        return _a;
+      })()
+      ? 'stuff'
+      : null
+    : null;
+}

__tests__/__fixtures__/complex/this/output.js

@@ -1,14 +1,12 @@
 function foo(array) {
-  return (() => {
-    const _fn = function (_value) {
-      return this && this.foo ? _value : null;
-    };
-    const _length = array.length;
-    const _results = Array(_length);
-    for (let _key = 0, _value; _key < _length; ++_key) {
-      _value = array[_key];
-      _results[_key] = _fn(_value, _key, array);
-    }
-    return _results;
-  })();
+  const _fn = function (_value) {
+    return this && this.foo ? _value : null;
+  };
+  const _length = array.length;
+  const _results = Array(_length);
+  for (let _key = 0, _value; _key < _length; ++_key) {
+    _value = array[_key];
+    _results[_key] = _fn(_value, _key, array);
+  }
+  return _results;
 }

src/utils.ts

@@ -165,7 +165,7 @@ export function replaceOrRemove(
   templates: ReturnType<typeof createTemplates>,
   replacement: Expression,
 ) {
-  if (shouldWrapInClosure(path, local)) {
+  if (shouldWrapInClosure(path)) {
     if (!t.isIdentifier(replacement, { name: 'undefined' })) {
       local.contents.push(t.returnStatement(replacement));
     }
@@ -214,49 +214,65 @@ export function isPossiblyDynamic(path: Path) {
   return path.isExpression();
 }
 
-export function shouldWrapInClosure(
-  path: Path<CallExpression>,
-  local: LocalReferences,
-): boolean {
+export function shouldWrapInClosure(path: Path): boolean {
   const parentPath = path.parentPath;
 
   if (!parentPath) {
     return false;
   }
 
-  const functionParent = path.getFunctionParent();
-
-  if (!functionParent) {
-    return isPossiblyDynamic(parentPath);
-  }
-
-  const grandparentPath = parentPath.parentPath;
-
-  if (parentPath.isPattern() || local.contents.length > 1) {
+  if (parentPath.isAssignmentPattern()) {
     return true;
   }
 
-  const contents = functionParent?.get('body')?.get('body');
-
-  if (Array.isArray(contents) && contents.length > 1) {
-    return contents.flat().some((content) => content.isVariableDeclaration());
-  }
-
-  if (!grandparentPath || !parentPath.isExpression()) {
-    return false;
+  if (
+    parentPath.isArrayExpression() ||
+    parentPath.isAwaitExpression() ||
+    parentPath.isBinaryExpression() ||
+    parentPath.isJSXElement() ||
+    parentPath.isJSXExpressionContainer() ||
+    parentPath.isObjectExpression() ||
+    parentPath.isObjectProperty() ||
+    parentPath.isUnaryExpression()
+  ) {
+    return shouldWrapInClosure(parentPath);
   }
 
-  const maybeNestedConditional = isPossiblyDynamic(grandparentPath);
-
   if (parentPath.isLogicalExpression()) {
     return (
-      !maybeNestedConditional && parentPath.get('right').node === path.node
+      !path.isCallExpression() ||
+      parentPath.get('right').node === path.node ||
+      shouldWrapInClosure(parentPath)
     );
   }
 
   if (parentPath.isConditionalExpression()) {
-    return !maybeNestedConditional && parentPath.get('test').node !== path.node;
+    return (
+      !path.isCallExpression() ||
+      parentPath.get('test').node !== path.node ||
+      shouldWrapInClosure(parentPath)
+    );
+  }
+
+  const functionParent = path.getFunctionParent();
+
+  if (
+    !functionParent ||
+    parentPath.node === functionParent.node ||
+    parentPath.parent === functionParent.node
+  ) {
+    return false;
+  }
+
+  if (
+    (parentPath.isReturnStatement() || parentPath.isExpressionStatement()) &&
+    parentPath.parentPath.isBlockStatement() &&
+    parentPath.parentPath.parent === functionParent.node
+  ) {
+    const body = functionParent.get('body.body');
+
+    return !Array.isArray(body) || body.length > 1;
   }
 
-  return maybeNestedConditional;
+  return true;
 }