Add tests and optimize spread

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@aet/tailwind",
-  "version": "0.0.1-beta.33",
+  "version": "0.0.1-beta.34",
   "license": "MIT",
   "scripts": {
     "build": "./scripts/index.ts",
@@ -37,6 +37,7 @@
     "postcss-nested": "^6.0.1",
     "prettier": "^3.3.2",
     "tailwindcss": "^3.4.4",
+    "tslib": "^2.6.3",
     "tsup": "^8.1.0",
     "typescript": "^5.5.3",
     "vite": "^5.3.2",

pnpm-lock.yaml

@@ -96,6 +96,9 @@ importers:
       tailwindcss:
         specifier: ^3.4.4
         version: 3.4.4
+      tslib:
+        specifier: ^2.6.3
+        version: 2.6.3
       tsup:
         specifier: ^8.1.0
         version: 8.1.0(postcss@8.4.39)(typescript@5.5.3)

src/__tests__/__snapshots__/attr.test.ts.snap

@@ -0,0 +1,46 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`attr > supports conditional expression in "css" attribute 1`] = `
+"// src/.temp-attr/index.tsx
+import { jsx } from "react/jsx-runtime";
+function Hello({
+  isCenter
+}) {
+  return /* @__PURE__ */ jsx("div", { className: isCenter ? "tw-gqn2k6" : void 0, children: "Hello, world!" });
+}
+export {
+  Hello
+};
+"
+`;
+
+exports[`attr > supports conditional expression in "css" attribute 2`] = `
+"/* babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-attr/index.css */
+.tw-gqn2k6 {
+  text-align: center;
+}
+"
+`;
+
+exports[`attr > supports grouped array css attribute 1`] = `
+"// src/.temp-attr/index.tsx
+import { jsx } from "react/jsx-runtime";
+function Hello() {
+  return /* @__PURE__ */ jsx("div", { className: "tw-gqn2k6 tw-1qtvvjy", children: "Hello, world!" });
+}
+export {
+  Hello
+};
+"
+`;
+
+exports[`attr > supports grouped array css attribute 2`] = `
+"/* babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-attr/index.css */
+.tw-gqn2k6 {
+  text-align: center;
+}
+.tw-1qtvvjy:hover {
+  font-weight: 600;
+}
+"
+`;

src/__tests__/__snapshots__/options.test.ts.snap

@@ -0,0 +1,21 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`options > supports custom jsxAttributeName 1`] = `
+"// src/.temp-options/index.tsx
+import { jsx } from "react/jsx-runtime";
+function Hello() {
+  return /* @__PURE__ */ jsx("div", { className: "tw-gqn2k6", children: "Hello, world!" });
+}
+export {
+  Hello
+};
+"
+`;
+
+exports[`options > supports custom jsxAttributeName 2`] = `
+"/* babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-options/index.css */
+.tw-gqn2k6 {
+  text-align: center;
+}
+"
+`;

src/__tests__/__snapshots__/spread.test.ts.snap

@@ -0,0 +1,51 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`spread > supports spread attribute in "css" attribute (2) 1`] = `
+"// src/.temp-spread/index.tsx
+import { cx as _cx } from "@emotion/css";
+import * as _tslib from "tslib";
+import { jsx } from "react/jsx-runtime";
+function Hello(props) {
+  props = {
+    ...props,
+    className: "text-center"
+  };
+  return /* @__PURE__ */ jsx("div", { ..._tslib.__rest(props, ["className"]), className: _cx("tw-gqn2k6", props.className), children: "Hello, world!" });
+}
+export {
+  Hello
+};
+"
+`;
+
+exports[`spread > supports spread attribute in "css" attribute (2) 2`] = `
+"/* babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-spread/index.css */
+.tw-gqn2k6 {
+  text-align: center;
+}
+"
+`;
+
+exports[`spread > supports spread attribute in "css" attribute 1`] = `
+"// src/.temp-spread/index.tsx
+import { cx as _cx } from "@emotion/css";
+import { jsx } from "react/jsx-runtime";
+function Hello({
+  className: _className,
+  ...props
+}) {
+  return /* @__PURE__ */ jsx("div", { ...props, className: _cx("tw-gqn2k6", _className), children: "Hello, world!" });
+}
+export {
+  Hello
+};
+"
+`;
+
+exports[`spread > supports spread attribute in "css" attribute 2`] = `
+"/* babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-spread/index.css */
+.tw-gqn2k6 {
+  text-align: center;
+}
+"
+`;

src/__tests__/__snapshots__/styleObject.test.ts.snap

@@ -0,0 +1,56 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`babel-tailwind > supports .hover, .focus, .active, .group-hover, .group-focus, .group-active 1`] = `
+"// babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-styleObject/index.tailwindStyle.js
+var tw_12x0ow0 = {
+  "&:focus": {
+    fontWeight: "700"
+  }
+};
+var tw_m4tg46 = {
+  "&:active": {
+    fontWeight: "300"
+  }
+};
+var tw_rqrjo3 = {
+  "&:hover:active": {
+    padding: "0.5rem"
+  }
+};
+var tw_1qtvvjy = {
+  "&:hover": {
+    fontWeight: "600"
+  }
+};
+
+// src/.temp-styleObject/index.tsx
+var style = [tw_1qtvvjy, tw_12x0ow0, tw_m4tg46, tw_rqrjo3];
+export {
+  style
+};
+"
+`;
+
+exports[`babel-tailwind > supports conversion into CSSProperties 1`] = `
+"// babel-tailwind:/Users/aet/Documents/Git/babel-tailwind/src/.temp-styleObject/index.tailwindStyle.js
+var tw_kt12th = {
+  padding: "0.5rem",
+  textAlign: "center",
+  "&:hover": {
+    fontWeight: "600"
+  },
+  "@media (min-width: 640px)": {
+    padding: "0.25rem"
+  }
+};
+
+// src/.temp-styleObject/index.tsx
+import { jsx } from "react/jsx-runtime";
+function Hello() {
+  return /* @__PURE__ */ jsx("div", { style: tw_kt12th, children: "Hello, world!" });
+}
+export {
+  Hello
+};
+"
+`;

src/__tests__/attr.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, it } from "vitest";
+import { getBuild } from "./utils";
+
+describe("attr", () => {
+  const compileESBuild = getBuild("attr");
+
+  it("supports grouped array css attribute", async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+        export function Hello() {
+          return (
+            <div css={["text-center", { hover: "font-semibold" }]}>
+              Hello, world!
+            </div>
+          );
+        }
+      `,
+    });
+
+    expect(files.js.text).toMatchSnapshot();
+    expect(files.css.text).toMatchSnapshot();
+  });
+
+  it('supports conditional expression in "css" attribute', async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+        export function Hello({ isCenter }) {
+          return (
+            <div css={isCenter ? "text-center" : undefined}>
+              Hello, world!
+            </div>
+          );
+        }
+      `,
+    });
+
+    expect(files.js.text).toMatchSnapshot();
+    expect(files.css.text).toMatchSnapshot();
+  });
+});

src/__tests__/merge.test.ts

@@ -0,0 +1,50 @@
+/* eslint-disable unicorn/string-content */
+import { describe, expect, it } from "vitest";
+import { getClassName } from "../index";
+import { getBuild } from "./utils";
+
+describe("merges with existing className attribute", () => {
+  const compileESBuild = getBuild("merge");
+
+  it("string literal", async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+        export function Hello() {
+          return (
+            <div className="text-center" css="text-center">
+              Hello, world!
+            </div>
+          );
+        }
+    `,
+    });
+
+    const clsName = getClassName("text-center");
+    expect(files.js.text).toContain(`className: "text-center ${clsName}"`);
+    expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
+  });
+
+  it("existing function", async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+        export function Hello() {
+          return (
+            <div className={({ isEntering }) => isEntering ? "enter" : "exit"} css="text-center">
+              Hello, world!
+            </div>
+          );
+        }
+      `,
+    });
+
+    const clsName = getClassName("text-center");
+    expect(files.js.text).toContain(
+      `className: ({\n    isEntering\n  }) => _cx(isEntering ? "enter" : "exit", "${clsName}")`
+    );
+    expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
+  });
+});

src/__tests__/options.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, it } from "vitest";
+import { getBuild } from "./utils";
+
+describe("options", () => {
+  const compileESBuild = getBuild("options");
+  it("supports custom jsxAttributeName", async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      jsxAttributeName: "tw",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+      export function Hello() {
+        return (
+          <div tw="text-center">
+            Hello, world!
+          </div>
+        );
+      }
+    `,
+    });
+
+    expect(files.js.text).toMatchSnapshot();
+    expect(files.css.text).toMatchSnapshot();
+  });
+
+  it("does not remove the attribute if `preserveAttribute` is true", async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      jsxAttributeAction: "preserve",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+        export function Hello() {
+          return (
+            <div css="text-center">
+              Hello, world!
+            </div>
+          );
+        }
+      `,
+    });
+
+    expect(files.js.text).toContain(`css: "text-center"`);
+  });
+});

src/__tests__/spread.test.ts

@@ -0,0 +1,46 @@
+/* eslint-disable unicorn/string-content */
+import { describe, expect, it } from "vitest";
+import { getBuild } from "./utils";
+
+describe("spread", () => {
+  const compileESBuild = getBuild("spread");
+
+  it('supports spread attribute in "css" attribute', async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+      export function Hello(props) {
+        return (
+          <div css="text-center" {...props}>
+            Hello, world!
+          </div>
+        );
+      }
+    `,
+    });
+
+    expect(files.js.text).toMatchSnapshot();
+    expect(files.css.text).toMatchSnapshot();
+  });
+
+  it('supports spread attribute in "css" attribute (2)', async () => {
+    const { files } = await compileESBuild({
+      clsx: "emotion",
+      expectFiles: 2,
+      javascript: /* tsx */ `
+      export function Hello(props) {
+        props = { ...props, className: "text-center" };
+        return (
+          <div css="text-center" {...props}>
+            Hello, world!
+          </div>
+        );
+      }
+    `,
+    });
+
+    expect(files.js.text).toMatchSnapshot();
+    expect(files.css.text).toMatchSnapshot();
+  });
+});

src/__tests__/styleObject.test.ts

@@ -1,6 +1,5 @@
 import { describe, expect, it } from "vitest";
 import { getBuild } from "./utils";
-import { getClassName } from "../index";
 
 describe("babel-tailwind", () => {
   const compileESBuild = getBuild("styleObject");
@@ -22,25 +21,7 @@ describe("babel-tailwind", () => {
     `,
     });
 
-    const clsName = getClassName("p-2 text-center hover:font-semibold sm:p-1").replace(
-      /^tw-/,
-      "tw_"
-    );
-    expect(files.js.text).toContain(
-      [
-        `var ${clsName} = {`,
-        '  padding: "0.5rem",',
-        '  textAlign: "center",',
-        '  "&:hover": {',
-        '    fontWeight: "600"',
-        "  },",
-        '  "@media (min-width: 640px)": {',
-        '    padding: "0.25rem"',
-        "  }",
-        "}",
-      ].join("\n")
-    );
-    expect(files.js.text).toContain(`style: ${clsName}`);
+    expect(files.js.text).toMatchSnapshot();
   });
 
   it("supports .hover, .focus, .active, .group-hover, .group-focus, .group-active", async () => {
@@ -59,34 +40,6 @@ describe("babel-tailwind", () => {
     `,
     });
 
-    const semibold = getClassName("hover:font-semibold").replace(/^tw-/, "tw_");
-    const bold = getClassName("focus:font-bold").replace(/^tw-/, "tw_");
-    const light = getClassName("active:font-light").replace(/^tw-/, "tw_");
-    const p = getClassName("active:hover:p-2").replace(/^tw-/, "tw_");
-
-    expect(files.js.text).toContain(
-      [
-        `var ${bold} = {`,
-        '  "&:focus": {',
-        '    fontWeight: "700"',
-        "  }",
-        "};",
-        `var ${light} = {`,
-        '  "&:active": {',
-        '    fontWeight: "300"',
-        "  }",
-        "};",
-        `var ${p} = {`,
-        '  "&:hover:active": {',
-        '    padding: "0.5rem"',
-        "  }",
-        "};",
-        `var ${semibold} = {`,
-        '  "&:hover": {',
-        '    fontWeight: "600"',
-        "  }",
-        "};",
-      ].join("\n")
-    );
+    expect(files.js.text).toMatchSnapshot();
   });
 });

src/__tests__/utils.ts

@@ -47,7 +47,7 @@ export function getBuild(name: string) {
     const result = await esbuild.build({
       bundle: true,
       write: false,
-      external: ["react/jsx-runtime", "@emotion/css", "clsx"],
+      external: ["react/jsx-runtime", "@emotion/css", "clsx", "tslib"],
       outdir: "dist",
       format: "esm",
       entryPoints: [await write("index.tsx", dedent(javascript))],

src/babel-tailwind.ts

@@ -28,6 +28,7 @@ export function babelTailwind(
 
   function getUtils(path: NodePath<t.Program>, state: b.PluginPass, t: BabelTypes) {
     let cx: t.Identifier;
+    let tslibImport: t.Identifier;
     let styleImport: t.Identifier;
 
     const cssMap = new Map<string, StyleMapEntry>();
@@ -87,6 +88,19 @@ export function babelTailwind(
         return t.cloneNode(cx);
       },
 
+      getTSlibImport: () => {
+        if (tslibImport == null) {
+          tslibImport = path.scope.generateUidIdentifier("tslib");
+          path.node.body.unshift(
+            t.importDeclaration(
+              [t.importNamespaceSpecifier(tslibImport)],
+              t.stringLiteral("tslib")
+            )
+          );
+        }
+        return t.cloneNode(tslibImport);
+      },
+
       finish(node: t.Program) {
         const { filename } = state;
         if (!cssMap.size && !jsMap.size) return;
@@ -279,12 +293,58 @@ export function babelTailwind(
           }
         }
       } else {
-        parent.attributes.push(
-          t.jsxAttribute(
-            t.jsxIdentifier("className"),
-            t.jSXExpressionContainer(valuePathNode)
-          )
-        );
+        const wrap = (originalValue: b.types.Expression) =>
+          t.callExpression(_.getCx(), [valuePathNode, originalValue]);
+
+        const rest = parent.attributes.filter(attr => t.isJSXSpreadAttribute(attr));
+        let arg;
+        if (rest.length === 1 && (arg = rest[0].argument) && t.isIdentifier(arg)) {
+          // props from argument and not modified anywhere
+          const scope = path.scope.getBinding(arg.name);
+          let index: number;
+          if (
+            scope &&
+            !scope.constantViolations.length &&
+            t.isFunctionDeclaration(scope.path.parent) &&
+            (index = (scope.path.parent.params as t.Node[]).indexOf(scope.path.node)) !==
+              -1
+          ) {
+            const clsVar = path.scope.generateUidIdentifier("className");
+            scope.path.parent.params[index] = t.objectPattern([
+              t.objectProperty(t.identifier("className"), clsVar),
+              t.restElement(scope.path.node as t.Identifier),
+            ]);
+
+            parent.attributes.push(
+              t.jsxAttribute(
+                t.jsxIdentifier("className"),
+                t.jsxExpressionContainer(wrap(clsVar))
+              )
+            );
+          } else {
+            const tslibImport = _.getTSlibImport();
+            rest[0].argument = t.callExpression(
+              t.memberExpression(tslibImport, t.identifier("__rest")),
+              [arg, t.arrayExpression([t.stringLiteral("className")])]
+            );
+
+            parent.attributes.push(
+              t.jsxAttribute(
+                t.jsxIdentifier("className"),
+                t.jsxExpressionContainer(
+                  wrap(t.memberExpression(arg, t.identifier("className")))
+                )
+              )
+            );
+          }
+        } else {
+          parent.attributes.push(
+            t.jsxAttribute(
+              t.jsxIdentifier("className"),
+              t.jsxExpressionContainer(valuePathNode)
+            )
+          );
+        }
       }
 
       if (jsxAttributeAction === "delete") {

src/index.test.ts

@@ -1,4 +1,3 @@
-/* eslint-disable unicorn/string-content */
 import { describe, expect, it } from "vitest";
 import { getClassName } from "./index";
 import { getBuild } from "./__tests__/utils";
@@ -25,137 +24,4 @@ describe("babel-tailwind", () => {
     expect(files.js.text).toContain(`className: "${clsName}"`);
     expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
   });
-
-  it("does not remove the attribute if `preserveAttribute` is true", async () => {
-    const { files } = await compileESBuild({
-      clsx: "emotion",
-      jsxAttributeAction: "preserve",
-      expectFiles: 2,
-      javascript: /* tsx */ `
-        export function Hello() {
-          return (
-            <div css="text-center">
-              Hello, world!
-            </div>
-          );
-        }
-      `,
-    });
-
-    expect(files.js.text).toContain(`css: "text-center"`);
-  });
-
-  describe('merges with existing "className" attribute', () => {
-    it("string literal", async () => {
-      const { files } = await compileESBuild({
-        clsx: "emotion",
-        expectFiles: 2,
-        javascript: /* tsx */ `
-          export function Hello() {
-            return (
-              <div className="text-center" css="text-center">
-                Hello, world!
-              </div>
-            );
-          }
-      `,
-      });
-
-      const clsName = getClassName("text-center");
-      expect(files.js.text).toContain(`className: "text-center ${clsName}"`);
-      expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
-    });
-
-    it("existing function", async () => {
-      const { files } = await compileESBuild({
-        clsx: "emotion",
-        expectFiles: 2,
-        javascript: /* tsx */ `
-          export function Hello() {
-            return (
-              <div className={({ isEntering }) => isEntering ? "enter" : "exit"} css="text-center">
-                Hello, world!
-              </div>
-            );
-          }
-        `,
-      });
-
-      const clsName = getClassName("text-center");
-      expect(files.js.text).toContain(
-        `className: ({\n    isEntering\n  }) => _cx(isEntering ? "enter" : "exit", "${clsName}")`
-      );
-      expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
-    });
-  });
-
-  it("supports custom jsxAttributeName", async () => {
-    const { files } = await compileESBuild({
-      clsx: "emotion",
-      jsxAttributeName: "tw",
-      expectFiles: 2,
-      javascript: /* tsx */ `
-        export function Hello() {
-          return (
-            <div tw="text-center">
-              Hello, world!
-            </div>
-          );
-        }
-      `,
-    });
-
-    const clsName = getClassName("text-center");
-    expect(files.js.text).toContain(`className: "${clsName}"`);
-    expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
-  });
-
-  it("supports grouped array css attribute", async () => {
-    const { files } = await compileESBuild({
-      clsx: "emotion",
-      expectFiles: 2,
-      javascript: /* tsx */ `
-        export function Hello() {
-          return (
-            <div css={["text-center", { hover: "font-semibold" }]}>
-              Hello, world!
-            </div>
-          );
-        }
-      `,
-    });
-
-    const clsName = ["text-center", "hover:font-semibold"].map(getClassName);
-    expect(files.js.text).toContain(`className: "${clsName.join(" ")}"`);
-    expect(files.css.text).toMatch(
-      [
-        `.${clsName[0]} {`,
-        "  text-align: center;",
-        "}",
-        `.${clsName[1]}:hover {`,
-        "  font-weight: 600;",
-        "}",
-      ].join("\n")
-    );
-  });
-
-  it('supports conditional expression in "css" attribute', async () => {
-    const { files } = await compileESBuild({
-      clsx: "emotion",
-      expectFiles: 2,
-      javascript: /* tsx */ `
-        export function Hello({ isCenter }) {
-          return (
-            <div css={isCenter ? "text-center" : undefined}>
-              Hello, world!
-            </div>
-          );
-        }
-      `,
-    });
-
-    const clsName = getClassName("text-center");
-    expect(files.js.text).toContain(`className: isCenter ? "${clsName}" : void 0`);
-    expect(files.css.text).toMatch(`.${clsName} {\n  text-align: center;\n}`);
-  });
 });