Merge pull request #105 from dancrumb/feat/#103

feat: 🎸 handle environment variable access

src/lib/builtins/__dirname.ts

@@ -0,0 +1,32 @@
+const DIRNAME_IS_USED = /(?:^|[\s\(\);=><{}\[\]\/:?,])__dirname(?:$|[^a-zA-Z0-9$_-])/;
+
+export const test = (sourceCode: string) => DIRNAME_IS_USED.test(sourceCode);
+
+export const modification = [
+    `const __dirname = (() => {`,
+    `    const { url: urlStr } = import.meta;`,
+    `    const url = new URL(urlStr);`,
+    `    const __filename = (url.protocol === "file:" ? url.pathname : urlStr)`,
+    `        .replace(/[/][^/]*$/, '');`,
+    ``,
+    `    const isWindows = (() => {`,
+    ``,
+    `        let NATIVE_OS: typeof Deno.build.os = "linux";`,
+    `        // eslint-disable-next-line @typescript-eslint/no-explicit-any`,
+    `        const navigator = (globalThis as any).navigator;`,
+    `        if (globalThis.Deno != null) {`,
+    `            NATIVE_OS = Deno.build.os;`,
+    `        } else if (navigator?.appVersion?.includes?.("Win") ?? false) {`,
+    `            NATIVE_OS = "windows";`,
+    `        }`,
+    ``,
+    `        return NATIVE_OS == "windows";`,
+    ``,
+    `    })();`,
+    ``,
+    `    return isWindows ?`,
+    `        __filename.split("/").join("\\\\").substring(1) :`,
+    `        __filename;`,
+    `})();`,
+    ``
+];

src/lib/builtins/__filename.ts

@@ -0,0 +1,31 @@
+const FILENAME_IS_USED = /(?:^|[\s\(\);=><{}\[\]\/:?,])__filename(?:$|[^a-zA-Z0-9$_-])/;
+
+export const test = (sourceCode: string) => FILENAME_IS_USED.test(sourceCode);
+
+export const modification = [
+    `const __filename = (() => {`,
+    `    const { url: urlStr } = import.meta;`,
+    `    const url = new URL(urlStr);`,
+    `    const __filename = (url.protocol === "file:" ? url.pathname : urlStr);`,
+    ``,
+    `    const isWindows = (() => {`,
+    ``,
+    `        let NATIVE_OS: typeof Deno.build.os = "linux";`,
+    `        // eslint-disable-next-line @typescript-eslint/no-explicit-any`,
+    `        const navigator = (globalThis as any).navigator;`,
+    `        if (globalThis.Deno != null) {`,
+    `            NATIVE_OS = Deno.build.os;`,
+    `        } else if (navigator?.appVersion?.includes?.("Win") ?? false) {`,
+    `            NATIVE_OS = "windows";`,
+    `        }`,
+    ``,
+    `        return NATIVE_OS == "windows";`,
+    ``,
+    `    })();`,
+    ``,
+    `    return isWindows ?`,
+    `        __filename.split("/").join("\\\\").substring(1) :`,
+    `        __filename;`,
+    `})();`,
+    ``
+];

src/lib/builtins/buffer.ts

@@ -0,0 +1,6 @@
+const BUFFER_IS_USED = /(?:^|[\s\(\);=><{}\[\]\/:?,])Buffer(?:$|[^a-zA-Z0-9$_-])/;
+const BUFFER_IS_IMPORTED = /import\s*{[^}]*Buffer[^}]*}\s*from\s*["'][^"']+["']/;
+
+export const test = (sourceCode: string) => BUFFER_IS_USED.test(sourceCode) && !BUFFER_IS_IMPORTED.test(sourceCode);
+
+export const modification = [`import { Buffer } from "buffer";`];

src/lib/builtins/index.ts

@@ -0,0 +1,15 @@
+import * as __dirname from "./__dirname";
+import * as __filename from "./__filename";
+import * as buffer from "./buffer";
+
+/**
+ * This is how we handle Node builtins
+ *
+ * Each module in this directory should export two functions:
+ * - test: (sourceCode: string) => boolean returns true if the source code needs to be modified because it refers to a Node builtin
+ * - modification: string[] the lines of code to prepend to the source code
+ */
+
+const builtins = [__filename, __dirname, buffer];
+
+export default builtins;

src/lib/denoifySingleFile.ts

@@ -1,6 +1,30 @@
 import { replaceAsync } from "../tools/replaceAsync";
 import type { denoifyImportExportStatementFactory } from "./denoifyImportExportStatement";
 import * as crypto from "crypto";
+import builtins from "./builtins/index";
+
+/**
+ * Remove any lines containing and following // @denoify-line-ignore
+ */
+const IGNORE_LINE_COMMENT = /^\/\/\s+@denoify-line-ignore/;
+function dealWithDenoifyLineIgnoreSpecialComment(sourceCode: string): string {
+    let previousLineHadIgnoreComment = false;
+    return sourceCode
+        .split("\n")
+        .filter(line => {
+            const thisLineHasIgnoreComment = IGNORE_LINE_COMMENT.test(line);
+            const skipThisLine = thisLineHasIgnoreComment || previousLineHadIgnoreComment;
+
+            if (previousLineHadIgnoreComment) {
+                previousLineHadIgnoreComment = false;
+            }
+            if (thisLineHasIgnoreComment) {
+                previousLineHadIgnoreComment = thisLineHasIgnoreComment;
+            }
+            return !skipThisLine;
+        })
+        .join("\n");
+}
 
 export function denoifySingleFileFactory(params: {} & ReturnType<typeof denoifyImportExportStatementFactory>) {
     const { denoifyImportExportStatement } = params;
@@ -9,96 +33,17 @@ export function denoifySingleFileFactory(params: {} & ReturnType<typeof denoifyI
     async function denoifySingleFile(params: { dirPath: string; sourceCode: string }): Promise<string> {
         const { dirPath, sourceCode } = params;
 
-        let modifiedSourceCode = sourceCode;
-
-        modifiedSourceCode = (function dealWithDenoifyLineIgnoreSpecialComment(sourceCode: string): string {
-            let split = sourceCode.split("\n");
-
-            split = split.map((line, i) => (i === split.length - 1 ? line : `${line}\n`));
-
-            const outSplit = [];
+        // Handle ignore comments
+        let modifiedSourceCode = dealWithDenoifyLineIgnoreSpecialComment(sourceCode);
 
-            for (let i = 0; i < split.length; i++) {
-                const line = split[i];
-
-                if (!line.startsWith("// @denoify-line-ignore")) {
-                    outSplit.push(line);
-                    continue;
-                }
-
-                i++;
+        // Add support for Node builtins
+        for (const builtin of builtins) {
+            if (builtin.test(modifiedSourceCode)) {
+                modifiedSourceCode = [...builtin.modification, modifiedSourceCode].join("\n");
             }
-
-            return outSplit.join("");
-        })(modifiedSourceCode);
-
-        if (usesBuiltIn("__filename", sourceCode)) {
-            modifiedSourceCode = [
-                `const __filename = (() => {`,
-                `    const { url: urlStr } = import.meta;`,
-                `    const url = new URL(urlStr);`,
-                `    const __filename = (url.protocol === "file:" ? url.pathname : urlStr);`,
-                ``,
-                `    const isWindows = (() => {`,
-                ``,
-                `        let NATIVE_OS: typeof Deno.build.os = "linux";`,
-                `        // eslint-disable-next-line @typescript-eslint/no-explicit-any`,
-                `        const navigator = (globalThis as any).navigator;`,
-                `        if (globalThis.Deno != null) {`,
-                `            NATIVE_OS = Deno.build.os;`,
-                `        } else if (navigator?.appVersion?.includes?.("Win") ?? false) {`,
-                `            NATIVE_OS = "windows";`,
-                `        }`,
-                ``,
-                `        return NATIVE_OS == "windows";`,
-                ``,
-                `    })();`,
-                ``,
-                `    return isWindows ?`,
-                `        __filename.split("/").join("\\\\").substring(1) :`,
-                `        __filename;`,
-                `})();`,
-                ``,
-                modifiedSourceCode
-            ].join("\n");
-        }
-
-        if (usesBuiltIn("__dirname", sourceCode)) {
-            modifiedSourceCode = [
-                `const __dirname = (() => {`,
-                `    const { url: urlStr } = import.meta;`,
-                `    const url = new URL(urlStr);`,
-                `    const __filename = (url.protocol === "file:" ? url.pathname : urlStr)`,
-                `        .replace(/[/][^/]*$/, '');`,
-                ``,
-                `    const isWindows = (() => {`,
-                ``,
-                `        let NATIVE_OS: typeof Deno.build.os = "linux";`,
-                `        // eslint-disable-next-line @typescript-eslint/no-explicit-any`,
-                `        const navigator = (globalThis as any).navigator;`,
-                `        if (globalThis.Deno != null) {`,
-                `            NATIVE_OS = Deno.build.os;`,
-                `        } else if (navigator?.appVersion?.includes?.("Win") ?? false) {`,
-                `            NATIVE_OS = "windows";`,
-                `        }`,
-                ``,
-                `        return NATIVE_OS == "windows";`,
-                ``,
-                `    })();`,
-                ``,
-                `    return isWindows ?`,
-                `        __filename.split("/").join("\\\\").substring(1) :`,
-                `        __filename;`,
-                `})();`,
-                ``,
-                modifiedSourceCode
-            ].join("\n");
-        }
-
-        if (usesBuiltIn("Buffer", sourceCode)) {
-            modifiedSourceCode = [`import { Buffer } from "buffer";`, modifiedSourceCode].join("\n");
         }
 
+        // Cleanup import/export statements
         const denoifiedImportExportStatementByHash = new Map<string, string>();
 
         for (const quoteSymbol of [`"`, `'`]) {
@@ -130,6 +75,16 @@ export function denoifySingleFileFactory(params: {} & ReturnType<typeof denoifyI
             }
         }
 
+        // Handle environment variable access
+        modifiedSourceCode = modifiedSourceCode.replaceAll(
+            /=\s+process.env(?:\.(?<varDot>\w+)|\[(?<q>['"])(?<varBracket>\w+)\k<q>\])/g,
+            `= Deno.env.get('$<varDot>$<varBracket>')`
+        );
+        modifiedSourceCode = modifiedSourceCode.replaceAll(
+            /process.env(?:\.(?<varDot>\w+)|\[(?<q>['"])(?<varBracket>\w+)\k<q>\])\s+=\s+(?<val>[^;]+)/g,
+            `Deno.env.set('$<varDot>$<varBracket>', $<val>)`
+        );
+
         for (const [hash, denoifiedImportExportStatement] of denoifiedImportExportStatementByHash) {
             modifiedSourceCode = modifiedSourceCode.replace(new RegExp(hash, "g"), denoifiedImportExportStatement);
         }
@@ -139,29 +94,3 @@ export function denoifySingleFileFactory(params: {} & ReturnType<typeof denoifyI
 
     return { denoifySingleFile };
 }
-
-/*
-TODO: This is really at proof of concept stage.
-
-In the current implementation if any of those keyword appear in the source
-regardless of the context (including comments) the polyfills will be included.
-
-For now this implementation will do the trick, priority goes to polyfilling the
-node's builtins but this need to be improved later on.
-
-*/
-function usesBuiltIn(builtIn: "__filename" | "__dirname" | "Buffer", sourceCode: string): boolean {
-    switch (builtIn) {
-        case "Buffer": {
-            //We should return false for example
-            //if we have an import from the browserify polyfill
-            //e.g.: import { Buffer } from "buffer";
-            if (!!sourceCode.match(/import\s*{[^}]*Buffer[^}]*}\s*from\s*["'][^"']+["']/)) {
-                return false;
-            }
-        }
-        case "__dirname":
-        case "__filename":
-            return new RegExp(`(?:^|[\\s\\(\\);=><{}\\[\\]\\/:?,])${builtIn}(?:$|[^a-zA-Z0-9$_-])`).test(sourceCode);
-    }
-}

test/denoifySingleFile.test.ts

@@ -322,6 +322,60 @@ Buffer_name
             "dirPath": ""
         });
 
+        expect(modifiedSourceCode).toBe(expected);
+    });
+    it("should access environment variables correctly", async () => {
+        const sourceCode = `const foo = process.env.FOO\nconst bar = process.env['BAR'];`;
+
+        const expected = `const foo = Deno.env.get('FOO')\nconst bar = Deno.env.get('BAR');`;
+
+        const { denoifySingleFile } = denoifySingleFileFactory({
+            "denoifyImportExportStatement": () => {
+                tsafeAssert(false);
+            }
+        });
+
+        const modifiedSourceCode = await denoifySingleFile({
+            sourceCode,
+            "dirPath": ""
+        });
+
+        expect(modifiedSourceCode).toBe(expected);
+    });
+    it("should set environment variables correctly", async () => {
+        const sourceCode = `process.env.FOO = 'foo';\nprocess.env['BAR'] = 22;`;
+
+        const expected = `Deno.env.set('FOO', 'foo');\nDeno.env.set('BAR', 22);`;
+
+        const { denoifySingleFile } = denoifySingleFileFactory({
+            "denoifyImportExportStatement": () => {
+                tsafeAssert(false);
+            }
+        });
+
+        const modifiedSourceCode = await denoifySingleFile({
+            sourceCode,
+            "dirPath": ""
+        });
+
+        expect(modifiedSourceCode).toBe(expected);
+    });
+    it("should update environment variables correctly", async () => {
+        const sourceCode = `process.env.FOO = process.env['BAR']+1;\nprocess.env['BAR'] = process.env.FOO + 'bar';`;
+
+        const expected = `Deno.env.set('FOO', Deno.env.get('BAR')+1);\nDeno.env.set('BAR', Deno.env.get('FOO') + 'bar');`;
+
+        const { denoifySingleFile } = denoifySingleFileFactory({
+            "denoifyImportExportStatement": () => {
+                tsafeAssert(false);
+            }
+        });
+
+        const modifiedSourceCode = await denoifySingleFile({
+            sourceCode,
+            "dirPath": ""
+        });
+
         expect(modifiedSourceCode).toBe(expected);
     });
 });

tsconfig.json

@@ -1,8 +1,7 @@
 {
     "compilerOptions": {
         "module": "commonjs",
-        "target": "ES2018",
-        "lib": ["es2018", "ES2019.Object"],
+        "target": "ES2021",
         "declaration": true,
         "outDir": "./dist",
         "sourceMap": true,