Everywhere: Hoist the Libraries folder to the top-level

Author: https://github.com/trflynn89
Commit: 93712b24bf
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2256
Reviewed-by: https://github.com/sideshowbarker

Libraries/LibDiff/Hunks.h

@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
+ * Copyright (c) 2023, Shannon Booth <shannon@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Assertions.h>
+#include <AK/Format.h>
+#include <AK/GenericLexer.h>
+#include <AK/String.h>
+#include <AK/StringView.h>
+#include <AK/Vector.h>
+
+namespace Diff {
+
+struct Range {
+    size_t start_line { 0 };
+    size_t number_of_lines { 0 };
+};
+
+struct HunkLocation {
+    Range old_range;
+    Range new_range;
+};
+
+struct Line {
+    enum class Operation {
+        Addition = '+',
+        Removal = '-',
+        Context = ' ',
+
+        // NOTE: This should only be used when deconstructing a hunk into old and new lines (context format)
+        Change = '!',
+    };
+
+    static constexpr Operation operation_from_symbol(char symbol)
+    {
+        switch (symbol) {
+        case '+':
+            return Operation::Addition;
+        case '-':
+            return Operation::Removal;
+        case ' ':
+            return Operation::Context;
+        default:
+            VERIFY_NOT_REACHED();
+        }
+    }
+
+    Operation operation;
+    String content;
+};
+
+struct Hunk {
+    HunkLocation location;
+    Vector<Line> lines;
+};
+
+enum class Format {
+    Unified,
+    Unknown,
+};
+
+struct Header {
+    Format format { Format::Unknown };
+
+    String old_file_path;
+    String new_file_path;
+};
+
+struct Patch {
+    Header header;
+    Vector<Hunk> hunks;
+};
+
+class Parser : public GenericLexer {
+public:
+    using GenericLexer::GenericLexer;
+
+    ErrorOr<Patch> parse_patch(Optional<size_t> const& strip_count = {});
+
+    ErrorOr<Vector<Hunk>> parse_hunks();
+
+private:
+    ErrorOr<Header> parse_header(Optional<size_t> const& strip_count);
+
+    ErrorOr<String> parse_file_line(Optional<size_t> const& strip_count);
+    Optional<HunkLocation> consume_unified_location();
+    bool consume_line_number(size_t& number);
+};
+
+ErrorOr<Vector<Hunk>> parse_hunks(StringView diff);
+
+}
+
+template<>
+struct AK::Formatter<Diff::Line::Operation> : Formatter<FormatString> {
+    ErrorOr<void> format(FormatBuilder& builder, Diff::Line::Operation operation)
+    {
+        return Formatter<FormatString>::format(builder, "{}"sv, static_cast<char>(operation));
+    }
+};
+
+template<>
+struct AK::Formatter<Diff::Line> : Formatter<FormatString> {
+    ErrorOr<void> format(FormatBuilder& builder, Diff::Line const& line)
+    {
+        return Formatter<FormatString>::format(builder, "{}{}"sv, line.operation, line.content);
+    }
+};
+
+template<>
+struct AK::Formatter<Diff::HunkLocation> : Formatter<FormatString> {
+    static ErrorOr<void> format(FormatBuilder& format_builder, Diff::HunkLocation const& location)
+    {
+        auto& builder = format_builder.builder();
+        TRY(builder.try_appendff("@@ -{}"sv, location.old_range.start_line));
+
+        if (location.old_range.number_of_lines != 1)
+            TRY(builder.try_appendff(",{}", location.old_range.number_of_lines));
+
+        TRY(builder.try_appendff(" +{}", location.new_range.start_line));
+
+        if (location.new_range.number_of_lines != 1)
+            TRY(builder.try_appendff(",{}", location.new_range.number_of_lines));
+
+        return builder.try_appendff(" @@");
+    }
+};