Improves string escaping during serialization (#5621)

**What's the problem this PR addresses?**

Positional arguments were over-complexified during serialization. For
example, `"foo bar"` was serialized as `$'foo bar'`. It works, but it's
a surprising syntax for users.

**How did you fix it?**

Since I needed to use the serialization to generate part of the new
website, I fixed it to make it look more natural, and added tests to
avoid regressions.

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(cherry picked from commit bbcce29)

Author: arcanis

.yarn/versions/d3925be6.yml

@@ -0,0 +1,11 @@
+releases:
+  "@yarnpkg/parsers": patch
+
+declined:
+  - "@yarnpkg/plugin-essentials"
+  - "@yarnpkg/plugin-nm"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/cli"
+  - "@yarnpkg/core"
+  - "@yarnpkg/sdks"
+  - "@yarnpkg/shell"

packages/yarnpkg-parsers/sources/shell.ts

@@ -82,22 +82,52 @@ export function stringifyValueArgument(argument: ValueArgument): string {
   return argument.segments.map(segment => stringifyArgumentSegment(segment)).join(``);
 }
 
+const ESCAPED_CONTROL_CHARS = new Map([
+  [`\f`, `\\f`],
+  [`\n`, `\\n`],
+  [`\r`, `\\r`],
+  [`\t`, `\\t`],
+  [`\v`, `\\v`],
+  [`\0`, `\\0`],
+]);
+
+const ESCAPED_DBL_CHARS = new Map([
+  [`\\`, `\\\\`],
+  [`$`, `\\$`],
+  [`"`, `\\"`],
+  ...Array.from(ESCAPED_CONTROL_CHARS, ([c, replacement]): [string, string] => {
+    return [c, `"$'${replacement}'"`];
+  }),
+]);
+
+const getEscapedControlChar = (c: string) => {
+  return ESCAPED_CONTROL_CHARS.get(c) ?? `\\x${c.charCodeAt(0).toString(16).padStart(2, `0`)}`;
+};
+
+const getEscapedDblChar = (match: string) => {
+  return ESCAPED_DBL_CHARS.get(match) ?? `"$'${getEscapedControlChar(match)}'"`;
+};
+
 export function stringifyArgumentSegment(argumentSegment: ArgumentSegment): string {
-  const doubleQuoteIfRequested = (string: string, quote: boolean) => quote ? `"${string}"` : string;
+  const doubleQuoteIfRequested = (string: string, quote: boolean) => quote
+    ? `"${string}"`
+    : string;
+
   const quoteIfNeeded = (text: string) => {
     if (text === ``)
-      return `""`;
-    if (!text.match(/[(){}<>$|&; \t"']/))
+      return `''`;
+
+    if (!text.match(/[()}<>$|&;"'\n\t ]/))
       return text;
-    return `$'${text
-      .replace(/\\/g, `\\\\`)
-      .replace(/'/g, `\\'`)
-      .replace(/\f/g, `\\f`)
-      .replace(/\n/g, `\\n`)
-      .replace(/\r/g, `\\r`)
-      .replace(/\t/g, `\\t`)
-      .replace(/\v/g, `\\v`)
-      .replace(/\0/g, `\\0`)}'`;
+
+    if (!text.match(/['\t\p{C}]/u))
+      return `'${text}'`;
+
+    if (!text.match(/'/)) {
+      return `$'${text.replace(/[\t\p{C}]/u, getEscapedControlChar)}'`;
+    } else {
+      return `"${text.replace(/["$\t\p{C}]/u, getEscapedDblChar)}"`;
+    }
   };
 
   switch (argumentSegment.type) {

packages/yarnpkg-parsers/tests/shell.test.ts

@@ -162,6 +162,9 @@ describe(`Shell parser`, () => {
 
 const STRINGIFIER_TESTS: Array<[string, string]> = [
   [`echo foo`, `echo foo`],
+  [`echo parapapa`, `echo parapapa`],
+  [`echo 'foo bar'`, `echo 'foo bar'`],
+  [`echo "foo' bar'"`, `echo "foo' bar'"`],
   [`echo foo; echo bar`, `echo foo; echo bar`],
   [`echo foo; echo bar;`, `echo foo; echo bar`],
   [`echo foo &`, `echo foo &`],
@@ -180,7 +183,7 @@ const STRINGIFIER_TESTS: Array<[string, string]> = [
   [`FOO=bar echo foo`, `FOO=bar echo foo`],
   [`FOO=bar BAZ=qux`, `FOO=bar BAZ=qux`],
   [`FOO=$'\\x09'`, `FOO=$'\\t'`],
-  [`FOO=$'\\u0027'`, `FOO=$'\\''`],
+  [`FOO=$'\\u0027'`, `FOO="'"`],
   [`FOO=$'\\U0001F601'`, `FOO=😁`],
 ];