StringUtil::extractLine (#989)

* Added extractLine line parsing to StringUtil. Use for matching lines instead of calcLines. calcLines uses extractLine to extract lines.
Fixed problems found in output of some tests- due to how a how final line is handled. Now a final line has a \r or \n\r combination, but nothing else after it, it is considered the last line (not the line after it).

* Use StringUtil::extractLine in slang-generate.

* Improved comment on extractLine

* Remove test code from StringUtil::extractLine

* Made StringUtil::extractLine act as if line terminators are 'separators'.
Added unit-test-string.cpp - to check behavior.

* Adding LineParser - not entirely necessary, but slightly easier to use.

* Improved LineParser::Iterator end testing.
Added improved tests for LineParser.

* Move line comparson after termination case - to fix problem with gcc release build.

* Make UnownedStringSlice handle comparison when begin is nullptr - as it uses memcmp and passing nullptr to memcmp is undefined, leading to optimizer being able to do some unfortunate optimizations on gcc.

1 files changed, 92 insertions, 0 deletions

diff --git a/tools/slang-test/unit-test-string.cpp b/tools/slang-test/unit-test-string.cpp
new file mode 100644
index 000000000..6110ca55e
--- /dev/null
+++ b/tools/slang-test/unit-test-string.cpp
@@ -0,0 +1,92 @@
+// unit-test-path.cpp
+
+#include "../../source/core/slang-string-util.h"
+
+#include "test-context.h"
+
+using namespace Slang;
+
+static bool _areEqual(const List<UnownedStringSlice>& lines, const UnownedStringSlice* checkLines, Int checkLinesCount)
+{
+    if (checkLinesCount != lines.getCount())
+    {
+        return false;
+    }
+
+    for (Int i = 0; i < checkLinesCount; ++i)
+    {
+        if (lines[i] != checkLines[i])
+        {
+            return false;
+        }
+    }
+    return true;
+}
+
+static bool _checkLines(const UnownedStringSlice& input, const UnownedStringSlice* checkLines, Int checkLinesCount)
+{
+    List<UnownedStringSlice> lines;
+    UnownedStringSlice text(input);
+    while (true)
+    {
+        UnownedStringSlice line = StringUtil::extractLine(text);
+        if (line.begin() == nullptr)
+        {
+            return _areEqual(lines, checkLines, checkLinesCount);
+        }
+        lines.add(line);
+    }
+}
+
+static bool _checkLineParser(const UnownedStringSlice& input)
+{
+    UnownedStringSlice remaining(input);
+    for (const auto line : LineParser(input))
+    {
+        UnownedStringSlice extractLine = StringUtil::extractLine(remaining);
+        if (line != extractLine)
+        {
+            return false;
+        }
+        // Handle hitting the end
+        if (line.begin() == nullptr || extractLine.begin() == nullptr)
+        {
+            return line.begin() == extractLine.begin();
+        }
+    }
+
+    return remaining.begin() == nullptr;
+}
+
+static void stringUnitTest()
+{
+    {
+        UnownedStringSlice checkLines[] = { UnownedStringSlice::fromLiteral("") };
+        SLANG_CHECK(_checkLines(UnownedStringSlice::fromLiteral(""), checkLines, SLANG_COUNT_OF(checkLines)));
+    }
+    {
+        // Will emit no lines
+        SLANG_CHECK(_checkLines(UnownedStringSlice(nullptr, nullptr), nullptr, 0));
+    }
+    {
+        // Two lines - both empty
+        UnownedStringSlice checkLines[] = { UnownedStringSlice(), UnownedStringSlice()};
+        SLANG_CHECK(_checkLines(UnownedStringSlice::fromLiteral("\n"), checkLines, SLANG_COUNT_OF(checkLines)));
+    }
+    {
+        UnownedStringSlice checkLines[] = { UnownedStringSlice::fromLiteral("Hello"), UnownedStringSlice::fromLiteral("World!") };
+        SLANG_CHECK(_checkLines(UnownedStringSlice::fromLiteral("Hello\nWorld!"), checkLines, SLANG_COUNT_OF(checkLines)));
+    }
+    {
+        UnownedStringSlice checkLines[] = { UnownedStringSlice::fromLiteral("Hello"), UnownedStringSlice::fromLiteral("World!"), UnownedStringSlice() };
+        SLANG_CHECK(_checkLines(UnownedStringSlice::fromLiteral("Hello\n\rWorld!\n"), checkLines, SLANG_COUNT_OF(checkLines)));
+    }
+
+    {
+        SLANG_CHECK(_checkLineParser(UnownedStringSlice::fromLiteral("Hello\n\rWorld!\n")));
+        SLANG_CHECK(_checkLineParser(UnownedStringSlice::fromLiteral("\n")));
+        SLANG_CHECK(_checkLineParser(UnownedStringSlice::fromLiteral("")));
+    }
+}
+
+SLANG_UNIT_TEST("String", stringUnitTest);