HAX: Try to fix the conpty first frame boog

microsoft · Aug 3, 2022 · aba6caf · aba6caf
1 parent ac9e9a3
commit aba6caf
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Showing 2 changed files with 35 additions and 4 deletions.
diff --git a/src/host/ut_host/ConptyOutputTests.cpp b/src/host/ut_host/ConptyOutputTests.cpp
@@ -121,6 +121,7 @@ class ConptyOutputTests
     TEST_METHOD(WriteAFewSimpleLines);
     TEST_METHOD(InvalidateUntilOneBeforeEnd);
     TEST_METHOD(SetConsoleTitleWithControlChars);
+    TEST_METHOD(IncludeBackgroundColorChangesInFirstFrame);
 
 private:
     bool _writeCallback(const char* const pch, const size_t cch);
@@ -371,6 +372,7 @@ void ConptyOutputTests::SetConsoleTitleWithControlChars()
 {
     BEGIN_TEST_METHOD_PROPERTIES()
         TEST_METHOD_PROPERTY(L"Data:control", L"{0x00, 0x0A, 0x1B, 0x80, 0x9B, 0x9C}")
+        TEST_METHOD_PROPERTY(L"IsolationLevel", L"Method")
     END_TEST_METHOD_PROPERTIES()
 
     int control;
@@ -400,3 +402,29 @@ void ConptyOutputTests::SetConsoleTitleWithControlChars()
 
     VERIFY_SUCCEEDED(renderer.PaintFrame());
 }
+
+void ConptyOutputTests::IncludeBackgroundColorChangesInFirstFrame()
+{
+    auto& g = ServiceLocator::LocateGlobals();
+    auto& renderer = *g.pRender;
+    auto& gci = g.getConsoleInformation();
+    auto& si = gci.GetActiveOutputBuffer();
+    auto& sm = si.GetStateMachine();
+
+    sm.ProcessString(L"\x1b[41mRun 1     \x1b[42mRun 2     \x1b[43mRun 3     \x1b[m");
+
+    expectedOutput.push_back("\x1b[2J"); // standard init sequence for the first frame
+    expectedOutput.push_back("\x1b[m"); // standard init sequence for the first frame
+    expectedOutput.push_back("\x1b[41m");
+    expectedOutput.push_back("\x1b[H"); // standard init sequence for the first frame
+    expectedOutput.push_back("Run 1     ");
+    expectedOutput.push_back("\x1b[42m");
+    expectedOutput.push_back("Run 2     ");
+    expectedOutput.push_back("\x1b[43m");
+    expectedOutput.push_back("Run 3     ");
+
+    // This is also part of the standard init sequence.
+    expectedOutput.push_back("\x1b[?25h");
+
+    VERIFY_SUCCEEDED(renderer.PaintFrame());
+}
diff --git a/src/renderer/vt/paint.cpp b/src/renderer/vt/paint.cpp
@@ -448,10 +448,13 @@ using namespace Microsoft::Console::Types;
     // the lines _wrapped_. It doesn't care to manually break the lines, but if
     // we trimmed the spaces off here, we'd print all the "~"s one after another
     // on the same line.
-    const auto removeSpaces = !lineWrapped && (useEraseChar ||
-                                               _clearedAllThisFrame ||
-                                               (_newBottomLine && printingBottomLine && bgMatched));
-    const auto cchActual = removeSpaces ? nonSpaceLength : cchLine;
+
+    const bool removeSpaces = !lineWrapped && (useEraseChar // we determined earlier that ECH is optimal
+                                               || (_clearedAllThisFrame && _lastTextAttributes == TextAttribute{}) // OR we cleared the last frame to the default attributes (specifically)
+                                               || (_newBottomLine && printingBottomLine && bgMatched)); // OR we just scrolled a new line onto the bottom of the screen with the correct attributes
+    const size_t cchActual = removeSpaces ?
+                                 (cchLine - numSpaces) :
+                                 cchLine;
 
     const auto columnsActual = removeSpaces ?
                                    (totalWidth - numSpaces) :