refactor(env): apply environment variables in cli

src/cli.ts

@@ -2,7 +2,7 @@
 import process from "node:process";
 import meow from "meow";
 import { $ } from "execa";
-import { applyEnvironmentVariables, getCommands } from "./helpers/index.js";
+import { parseEnvironmentVariables, getCommands } from "./helpers/index.js";
 import { getTasks } from "./tasks.js";
 
 const cli = meow(`
@@ -69,7 +69,12 @@ if (input.length === 0 || helpShortFlag) {
 
 const { hideTimer, persist: persistentOutput, allOptional, environment } = cli.flags;
 
-applyEnvironmentVariables(environment);
+const env = parseEnvironmentVariables(environment);
+
+process.env = {
+	...process.env,
+	...env,
+};
 
 const tasks = getTasks({
 	commands: getCommands(input),

src/helpers/index.ts

@@ -1,4 +1,4 @@
 export * from "./get-commands/index.js";
 export * from "./tasks/index.js";
-export * from "./apply-environment-variables.js";
+export * from "./parse-environment-variables.js";
 export type * from "./types.js";

src/helpers/apply-environment-variables.ts → src/helpers/parse-environment-variables.ts

@@ -1,4 +1,3 @@
-import process from "node:process";
 import type { MatchAll } from "./types.js";
 
 /**
@@ -16,7 +15,7 @@ import type { MatchAll } from "./types.js";
 const environmentVariableRegex = /(?=[^,])(?<env>[^:,]*)(?::["'](?<quoted>[^"']*)["']|:(?<value>[^,]*))?/g;
 
 /**
- * Parses environment variable input into separate values, applying them to `process.env`.
+ * Parses environment variable input into separate values.
  *
  * Separates values by comma. Values are set to `"true"`. If a value has a `:`,
  * it will be split and set to the value following the `:`. Commas in values must be quoted.
@@ -25,21 +24,26 @@ const environmentVariableRegex = /(?=[^,])(?<env>[^:,]*)(?::["'](?<quoted>[^"']*
  * @example
  * // listr -e FOO -e BAR,LIST:\"a,b,c\",FOO,BAR:\'baz\' -e FIZZ:'buzz bazz'
  * applyEnvironmentVariables(["FOO", "BAR,LIST:\"a,b,c\",FOO,BAR:'baz'", "FIZZ:buzz bazz"]);
- *
- * process.env.FOO = "true";
- * process.env.BAR = "baz";
- * process.env.LIST = "a,b,c";
- * process.env.FIZZ = "buzz bazz";
+ * //=> {
+ * //=>   FOO: "true",
+ * //=>   BAR: "baz",
+ * //=>   LIST: "a,b,c",
+ * //=>   FIZZ: "buzz bazz",
+ * //=> }
  */
-export const applyEnvironmentVariables = (environment: string[]) => {
+export const parseEnvironmentVariables = (environment: string[]): Record<string, string> => {
+	const parsedEnvironmentVariables: Record<string, string> = {};
+
 	for (const argument of environment) {
 		const pairs = argument.matchAll(environmentVariableRegex) as MatchAll<"env", "quoted" | "value">;
 
 		for (const pair of pairs) {
 			const key = pair.groups.env;
 			const value = pair.groups.quoted ?? pair.groups.value;
 
-			process.env[key] = value ?? String(true);
+			parsedEnvironmentVariables[key] = value ?? String(true);
 		}
 	}
+
+	return parsedEnvironmentVariables;
 };

test/helpers/apply-environment-variables.ts → test/helpers/parse-environment-variables.ts

@@ -1,33 +1,19 @@
 /* eslint-disable @typescript-eslint/naming-convention */
-import process from "node:process";
-import anyTest, { type TestFn } from "ava";
-import { applyEnvironmentVariables } from "../../src/helpers/apply-environment-variables.js";
-
-const test = anyTest as TestFn<{
-	originalProcessEnv: typeof process["env"];
-}>;
-
-test.beforeEach("reset process.env", t => {
-	t.context.originalProcessEnv = process.env;
-	process.env = {};
-});
-
-test.after("reapply process.env", t => {
-	process.env = t.context.originalProcessEnv;
-});
+import test from "ava";
+import { parseEnvironmentVariables } from "../../src/helpers/parse-environment-variables.js";
 
 type MacroArgs = {
 	env_Vars: string[];
 	expected: string[] | Record<string, string>;
 };
 
 const verifyEnv = test.macro((t, { env_Vars: input, expected }: MacroArgs) => {
-	applyEnvironmentVariables(input);
+	const env = parseEnvironmentVariables(input);
 
 	if (Array.isArray(expected)) {
-		t.deepEqual(Object.keys(process.env), expected);
+		t.deepEqual(Object.keys(env), expected);
 	} else {
-		t.deepEqual(process.env, expected);
+		t.deepEqual(env, expected);
 	}
 });