Public commit

scripts/plugins/babel-dynamic-import.ts

@@ -0,0 +1,54 @@
+import { dirname } from "path"
+import glob from "fast-glob"
+import type { types } from "@babel/core"
+import type { BabelPlugin } from "./esbuild-babel"
+
+const skip = new WeakSet<types.CallExpression>()
+
+export const dynamicImport =
+  (filePath: string): BabelPlugin =>
+  ({ types: t }) => ({
+    name: "dynamic-import",
+    visitor: {
+      Import(path) {
+        if (
+          !t.isCallExpression(path.parent) ||
+          path.parent.arguments.length !== 1 ||
+          skip.has(path.parent)
+        ) {
+          return
+        }
+
+        const [arg] = path.parent.arguments
+        if (!t.isTemplateLiteral(arg)) {
+          return
+        }
+
+        const key = path.scope.generateDeclaredUidIdentifier("key")
+
+        const globText = arg.quasis.map(x => x.value.raw).join("*")
+        const globCandidates = glob.sync(globText, {
+          cwd: dirname(filePath),
+        })
+
+        const clone = t.cloneNode(path.parent, true)
+        skip.add(clone)
+
+        const cond = globCandidates.reduceRight(
+          (accum: types.Expression, cur) =>
+            t.conditionalExpression(
+              t.binaryExpression("===", key, t.stringLiteral(cur)),
+              t.callExpression(t.import(), [t.stringLiteral(cur)]),
+              accum,
+            ),
+          clone,
+        )
+
+        t.cloneNode(path.parent)
+
+        path.parentPath.replaceWith(
+          t.sequenceExpression([t.assignmentExpression("=", key, arg), cond]),
+        )
+      },
+    },
+  })