From 1b362140ae789cd79a3495b991bba6203957e507 Mon Sep 17 00:00:00 2001
From: elsid <elsid.mail@gmail.com>
Date: Sun, 7 Sep 2025 17:42:48 +0200
Subject: [PATCH] Remove duplicated and leading slashes in
 normalizeFilenameInPlace

To be consistent with correctResourcePath.
---
 apps/components_tests/vfs/testpathutil.cpp | 57 ++++++++++++++++++++--
 components/misc/resourcehelpers.cpp        |  9 ----
 components/vfs/pathutil.hpp                | 53 +++++++++++++++++---
 3 files changed, 99 insertions(+), 20 deletions(-)

diff --git a/apps/components_tests/vfs/testpathutil.cpp b/apps/components_tests/vfs/testpathutil.cpp
index 771036d60c..c30f563a4d 100644
--- a/apps/components_tests/vfs/testpathutil.cpp
+++ b/apps/components_tests/vfs/testpathutil.cpp
@@ -10,6 +10,49 @@ namespace VFS::Path
     {
         using namespace testing;
 
+        struct VFSPathIsNormalizedTest : TestWithParam<std::pair<std::string_view, bool>>
+        {
+        };
+
+        TEST_P(VFSPathIsNormalizedTest, shouldReturnExpectedResult)
+        {
+            EXPECT_EQ(isNormalized(GetParam().first), GetParam().second);
+        }
+
+        const std::pair<std::string_view, bool> isNormalizedTestParams[] = {
+            { std::string_view(), true },
+            { "foo", true },
+            { "foo/bar", true },
+            { "foo/bar/baz", true },
+            { "/foo", false },
+            { "foo//", false },
+            { "foo\\", false },
+            { "Foo", false },
+        };
+
+        INSTANTIATE_TEST_SUITE_P(IsNormalizedTestParams, VFSPathIsNormalizedTest, ValuesIn(isNormalizedTestParams));
+
+        TEST(VFSPathNormalizeFilenameInPlaceTest, shouldRemoveLeadingSeparators)
+        {
+            std::string value("//foo");
+            normalizeFilenameInPlace(value);
+            EXPECT_EQ(value, "foo");
+        }
+
+        TEST(VFSPathNormalizeFilenameInPlaceTest, shouldRemoveDuplicatedSeparators)
+        {
+            std::string value("foo//bar///baz");
+            normalizeFilenameInPlace(value);
+            EXPECT_EQ(value, "foo/bar/baz");
+        }
+
+        TEST(VFSPathNormalizeFilenameInPlaceTest, shouldRemoveDuplicatedLeadingSeparator)
+        {
+            std::string value("//foo");
+            normalizeFilenameInPlace(value);
+            EXPECT_EQ(value, "foo");
+        }
+
         TEST(VFSPathNormalizedTest, shouldSupportDefaultConstructor)
         {
             const Normalized value;
@@ -79,6 +122,13 @@ namespace VFS::Path
             EXPECT_EQ(value.value(), "foo/bar/baz");
         }
 
+        TEST(VFSPathNormalizedTest, operatorDivShouldNormalizeSuffix)
+        {
+            Normalized value("foo/bar");
+            value /= std::string_view("\\A\\\\B");
+            EXPECT_EQ(value.value(), "foo/bar/a/b");
+        }
+
         TEST(VFSPathNormalizedTest, changeExtensionShouldReplaceAfterLastDot)
         {
             Normalized value("foo/bar.a");
@@ -86,11 +136,10 @@ namespace VFS::Path
             EXPECT_EQ(value.value(), "foo/bar.so");
         }
 
-        TEST(VFSPathNormalizedTest, changeExtensionShouldNormalizeExtension)
+        TEST(VFSPathNormalizedTest, changeExtensionShouldThrowExceptionOnNotNormalizedExtension)
         {
             Normalized value("foo/bar.a");
-            ASSERT_TRUE(value.changeExtension("SO"));
-            EXPECT_EQ(value.value(), "foo/bar.so");
+            EXPECT_THROW(value.changeExtension("\\SO"), std::invalid_argument);
         }
 
         TEST(VFSPathNormalizedTest, changeExtensionShouldIgnorePathWithoutADot)
@@ -116,7 +165,7 @@ namespace VFS::Path
         TEST(VFSPathNormalizedTest, changeExtensionShouldThrowExceptionOnExtensionWithSeparator)
         {
             Normalized value("foo.a");
-            EXPECT_THROW(value.changeExtension("/so"), std::invalid_argument);
+            EXPECT_THROW(value.changeExtension("so/"), std::invalid_argument);
         }
 
         template <class T>
diff --git a/components/misc/resourcehelpers.cpp b/components/misc/resourcehelpers.cpp
index 9b0e81dc59..0a9ac84168 100644
--- a/components/misc/resourcehelpers.cpp
+++ b/components/misc/resourcehelpers.cpp
@@ -1,6 +1,5 @@
 #include "resourcehelpers.hpp"
 
-#include <algorithm>
 #include <sstream>
 #include <string_view>
 
@@ -39,14 +38,6 @@ std::string Misc::ResourceHelpers::correctResourcePath(std::span<const std::stri
 {
     std::string correctedPath = VFS::Path::normalizeFilename(resPath);
 
-    // Flatten slashes
-    auto bothSeparators = [](char a, char b) { return a == VFS::Path::separator && b == VFS::Path::separator; };
-    correctedPath.erase(std::unique(correctedPath.begin(), correctedPath.end(), bothSeparators), correctedPath.end());
-
-    // Remove leading separator
-    if (!correctedPath.empty() && correctedPath[0] == VFS::Path::separator)
-        correctedPath.erase(0, 1);
-
     // Handle top level directory
     bool needsPrefix = true;
     for (std::string_view potentialTopLevelDirectory : topLevelDirectories)
diff --git a/components/vfs/pathutil.hpp b/components/vfs/pathutil.hpp
index a890be8a54..d31f840f7a 100644
--- a/components/vfs/pathutil.hpp
+++ b/components/vfs/pathutil.hpp
@@ -14,24 +14,59 @@ namespace VFS::Path
     inline constexpr char separator = '/';
     inline constexpr char extensionSeparator = '.';
 
-    inline constexpr char normalize(char c)
+    [[nodiscard]] inline constexpr char normalize(char c)
     {
         return c == '\\' ? separator : Misc::StringUtils::toLower(c);
     }
 
-    inline constexpr bool isNormalized(std::string_view name)
+    [[nodiscard]] inline constexpr bool isNormalized(std::string_view name)
     {
-        return std::all_of(name.begin(), name.end(), [](char v) { return v == normalize(v); });
+        if (name.empty())
+            return true;
+
+        if (name.front() != normalize(name.front()))
+            return false;
+
+        if (name.front() == separator)
+            return false;
+
+        for (std::size_t i = 1, n = name.size(); i < n; ++i)
+        {
+            if (name[i] != normalize(name[i]))
+                return false;
+
+            if (name[i] == separator && name[i - 1] == name[i])
+                return false;
+        }
+
+        return true;
     }
 
-    inline void normalizeFilenameInPlace(auto begin, auto end)
+    [[nodiscard]] inline auto removeDuplicatedSeparators(auto begin, auto end)
+    {
+        return std::unique(begin, end, [](char a, char b) { return a == separator && b == separator; });
+    }
+
+    [[nodiscard]] inline auto removeLeadingSeparator(auto begin, auto end)
+    {
+        if (begin != end && *begin == separator)
+            return begin + 1;
+        return begin;
+    }
+
+    [[nodiscard]] inline auto normalizeFilenameInPlace(auto begin, auto end)
     {
         std::transform(begin, end, begin, normalize);
+        end = removeDuplicatedSeparators(begin, end);
+        begin = removeLeadingSeparator(begin, end);
+        return std::pair(begin, end);
     }
 
     inline void normalizeFilenameInPlace(std::string& name)
     {
-        normalizeFilenameInPlace(name.begin(), name.end());
+        const auto [begin, end] = normalizeFilenameInPlace(name.begin(), name.end());
+        name.erase(end, name.end());
+        name.erase(name.begin(), begin);
     }
 
     /// Normalize the given filename, making slashes/backslashes consistent, and lower-casing.
@@ -197,6 +232,8 @@ namespace VFS::Path
 
         bool changeExtension(std::string_view extension)
         {
+            if (!isNormalized(extension))
+                throw std::invalid_argument("Not normalized extension: " + std::string(extension));
             if (findSeparatorOrExtensionSeparator(extension.begin(), extension.end()) != extension.end())
                 throw std::invalid_argument("Invalid extension: " + std::string(extension));
             const auto it = findSeparatorOrExtensionSeparator(mValue.rbegin(), mValue.rend());
@@ -204,7 +241,7 @@ namespace VFS::Path
                 return false;
             const std::string::difference_type pos = mValue.rend() - it;
             mValue.replace(pos, mValue.size(), extension);
-            normalizeFilenameInPlace(mValue.begin() + pos, mValue.end());
+            std::transform(mValue.begin() + pos, mValue.end(), mValue.begin() + pos, normalize);
             return true;
         }
 
@@ -230,7 +267,9 @@ namespace VFS::Path
             mValue += separator;
             const std::size_t offset = mValue.size();
             mValue += value;
-            normalizeFilenameInPlace(mValue.begin() + offset, mValue.end());
+            const auto [begin, end] = normalizeFilenameInPlace(mValue.begin() + offset, mValue.end());
+            std::copy(begin, end, mValue.begin() + offset);
+            mValue.resize(offset + (end - begin));
             return *this;
         }