fix: do not mutate process.argv (#36)

* (fix): don't mutate process.argv with arr.splice

- 1.7.1 introduced some arr.splice's into the code, which caused
  mutations in process.argv, affecting downstream code

- set arr to a clone of process.argv instead so it can be freely
  mutated after
- explicitly call the parameter processArgv so code is written more
  carefully when dealing with it
- add a test to ensure process.argv is not mutated

* chore: truncate

* chore: add & improve tests

Co-authored-by: Luke Edwards <[email protected]>

Author: agilgur5

lib/index.js

@@ -106,6 +106,7 @@ class Sade {
 	}
 
 	parse(arr, opts={}) {
+		arr = arr.slice(); // copy
 		let offset=2, tmp, idx, isVoid, cmd;
 		let alias = { h:'help', v:'version' };
 		let argv = mri(arr.slice(offset), { alias });

test/index.js

@@ -212,6 +212,70 @@ test('prog.action (multi optional)', t => {
 	(c=true) && run(); // +4 tests
 });
 
+test('prog.parse :: safe :: default', t => {
+	let ctx = sade('foo').command('build', '', { default: true });
+
+	let argv1 = ['', '', 'build'];
+	let foo = ctx.parse(argv1, { lazy: true });
+	t.deepEqual(argv1, ['', '', 'build'], '~> argv unchanged');
+	t.deepEqual(foo.args, [{ _: [] }], '~> args correct');
+
+	let argv2 = ['', ''];
+	let bar = ctx.parse(argv2, { lazy: true });
+	t.deepEqual(argv2, ['', ''], '~> argv unchanged');
+	t.deepEqual(bar.args, [{ _: [] }], '~> args correct');
+
+	t.end();
+});
+
+test('prog.parse :: safe :: alias', t => {
+	let ctx = sade('foo').command('build').alias('b');
+
+	let argv1 = ['', '', 'build'];
+	let foo = ctx.parse(argv1, { lazy: true });
+	t.deepEqual(argv1, ['', '', 'build'], '~> argv unchanged');
+	t.deepEqual(foo.args, [{ _: [] }], '~> args correct');
+
+	let argv2 = ['', '', 'b'];
+	let bar = ctx.parse(argv2, { lazy: true });
+	t.deepEqual(argv2, ['', '', 'b'], '~> argv unchanged');
+	t.deepEqual(bar.args, [{ _: [] }], '~> args correct');
+
+	t.end();
+});
+
+test('prog.parse :: safe :: default :: flags', t => {
+	let ctx = sade('foo').command('build <dir>', '', { default: true });
+
+	let argv1 = ['', '', '-r', 'dotenv', 'build', 'public', '--fresh'];
+	let foo = ctx.parse(argv1, { lazy: true });
+	t.deepEqual(argv1, ['', '', '-r', 'dotenv', 'build', 'public', '--fresh'], '~> argv unchanged');
+	t.deepEqual(foo.args, ['public', { _: [], r: 'dotenv', fresh: true }], '~> args correct');
+
+	let argv2 = ['', '', '-r', 'dotenv', 'public', '--fresh'];
+	let bar = ctx.parse(argv2, { lazy: true });
+	t.deepEqual(argv2, ['', '', '-r', 'dotenv', 'public', '--fresh'], '~> argv unchanged');
+	t.deepEqual(bar.args, ['public', { _: [], r: 'dotenv', fresh: true }], '~> args correct');
+
+	t.end();
+});
+
+test('prog.parse :: safe :: alias :: flags', t => {
+	let ctx = sade('foo').command('build <dir>').alias('b');
+
+	let argv1 = ['', '', '-r', 'dotenv', 'build', 'public', '--fresh'];
+	let foo = ctx.parse(argv1, { lazy: true });
+	t.deepEqual(argv1, ['', '', '-r', 'dotenv', 'build', 'public', '--fresh'], '~> argv unchanged');
+	t.deepEqual(foo.args, ['public', { _: [], r: 'dotenv', fresh: true }], '~> args correct');
+
+	let argv2 = ['', '', '-r', 'dotenv', 'b', 'public', '--fresh'];
+	let bar = ctx.parse(argv2, { lazy: true });
+	t.deepEqual(argv2, ['', '', '-r', 'dotenv', 'b', 'public', '--fresh'], '~> argv unchanged');
+	t.deepEqual(bar.args, ['public', { _: [], r: 'dotenv', fresh: true }], '~> args correct');
+
+	t.end();
+});
+
 test('prog.parse :: lazy', t => {
 	t.plan(14);