✅ add qs.js comparison

Author: techouse

.swiftlint.yml

@@ -9,6 +9,7 @@ excluded:
   - Bench
   - ObjCE2ETests
   - Tests
+  - Tools
 
 disabled_rules:
   - trailing_whitespace

.vscode/launch.json

@@ -1,4 +1,23 @@
 {
     "version": "0.2.0",
-    "configurations": []
+    "configurations": [
+        {
+            "type": "swift",
+            "request": "launch",
+            "args": [],
+            "cwd": "${workspaceFolder:QsSwift}",
+            "name": "Debug QsSwiftComparison",
+            "program": "${workspaceFolder:QsSwift}/.build/debug/QsSwiftComparison",
+            "preLaunchTask": "swift: Build Debug QsSwiftComparison"
+        },
+        {
+            "type": "swift",
+            "request": "launch",
+            "args": [],
+            "cwd": "${workspaceFolder:QsSwift}",
+            "name": "Release QsSwiftComparison",
+            "program": "${workspaceFolder:QsSwift}/.build/release/QsSwiftComparison",
+            "preLaunchTask": "swift: Build Release QsSwiftComparison"
+        }
+    ]
 }

Package.swift

@@ -48,5 +48,10 @@ let package = Package(
             ],
             path: "Tests/QsObjCTests"
         ),
+        .executableTarget(
+            name: "QsSwiftComparison",
+            dependencies: ["QsSwift"],
+            path: "Tools/QsSwiftComparison"
+        ),
     ]
 )

Package@swift-5.10.swift

@@ -61,5 +61,10 @@ let package = Package(
             ],
             path: "Tests/QsObjCTests"
         ),
+        .executableTarget(
+            name: "QsSwiftComparison",
+            dependencies: ["QsSwift"],
+            path: "Tools/QsSwiftComparison"
+        ),
     ]
 )

Tools/QsSwiftComparison/compare_outputs.sh

@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+export SWIFT_DETERMINISTIC_HASHING=1
+
+script_dir="$(cd "$(dirname "$0")" && pwd)"
+
+# Canonicalize query strings by sorting key-value pairs so order differences
+# don't cause spurious diffs. This mirrors how we compare semantics, not order.
+canonicalize_query() {
+  local qs="$1"
+  local IFS='&'
+  # Split on '&' into an array (bash 3-compatible). Predeclare to avoid
+  # "unbound variable" under `set -u` when the input is empty.
+  local -a parts=()
+  # Only split when the string is non-empty; otherwise leave as empty array.
+  if [[ -n "$qs" ]]; then
+    read -r -a parts <<< "$qs"
+  fi
+  # If there are no parts, return an empty string so callers print `Encoded: `
+  # without tripping `set -u` on ${parts[@]}.
+  if ((${#parts[@]} == 0)); then
+    echo ""
+    return
+  fi
+  # Sort pairs lexicographically in a C locale and join back with '&'
+  LC_ALL=C printf '%s\n' "${parts[@]}" | sort | paste -sd '&' -
+}
+
+# For lines like `Decoded: { ... }`, recursively sort object keys so
+# JSON key ordering differences don't cause spurious diffs.
+# Uses Node (already a dependency for the comparison).
+canonicalize_json_with_node() {
+  node - <<'NODE'
+let s = "";
+process.stdin.on("data", c => (s += c));
+process.stdin.on("end", () => {
+  function sort(v) {
+    if (Array.isArray(v)) return v.map(sort);
+    if (v && typeof v === "object") {
+      const keys = Object.keys(v).sort();
+      const o = {};
+      for (const k of keys) o[k] = sort(v[k]);
+      return o;
+    }
+    return v;
+  }
+  try {
+    const v = JSON.parse(s);
+    process.stdout.write(JSON.stringify(sort(v)));
+  } catch {
+    process.stdout.write(s);
+  }
+});
+NODE
+}
+
+normalize_stream() {
+  local line
+  while IFS= read -r line; do
+    if [[ "$line" == Encoded:* ]]; then
+      local qs="${line#Encoded: }"
+      echo "Encoded: $(canonicalize_query "$qs")"
+    elif [[ "$line" == Decoded:* ]]; then
+      local json="${line#Decoded: }"
+      local canon
+      canon="$(printf '%s' "$json" | canonicalize_json_with_node)"
+      echo "Decoded: $canon"
+    else
+      echo "$line"
+    fi
+  done
+}
+
+node_output_raw="$(node "$script_dir/js/qs.js")"
+swift_output_raw="$(swift run -q -c release QsSwiftComparison)"
+
+# Normalize both outputs to remove ordering noise.
+node_output="$(printf '%s\n' "$node_output_raw" | normalize_stream)"
+swift_output="$(printf '%s\n' "$swift_output_raw" | normalize_stream)"
+
+if [ "$node_output" == "$swift_output" ]; then
+  echo "The outputs are identical."
+  exit 0
+else
+  echo "The outputs are different."
+  diff -u <(echo "$node_output") <(echo "$swift_output") || true
+  exit 1
+fi

Tools/QsSwiftComparison/js/.gitignore

@@ -0,0 +1,2 @@
+node_modules
+package-lock.json

Tools/QsSwiftComparison/js/package.json

@@ -0,0 +1,10 @@
+{
+    "name": "qs_comparison",
+    "version": "1.0.0",
+    "description": "A comparison of query string parsing libraries",
+    "author": "Klemen Tusar",
+    "license": "BSD-3-Clause",
+    "dependencies": {
+        "qs": "^6.14.0"
+    }
+}

Tools/QsSwiftComparison/js/qs.js

@@ -0,0 +1,12 @@
+const fs = require('fs');
+const path = require('path');
+const qs = require('qs');
+
+// Use path.join to combine __dirname with the relative path to test_cases.json
+const filePath = path.join(__dirname, 'test_cases.json');
+const e2eTestCases = JSON.parse(fs.readFileSync(filePath).toString());
+
+e2eTestCases.forEach(testCase => {
+    console.log('Encoded:', qs.stringify(testCase.data));
+    console.log('Decoded:', JSON.stringify(qs.parse(testCase.encoded)));
+});