PatchContent shows changes only for selected file if size of patch te…

…xt exceeds configured limit.

Added configuration option "Max patch size MiB".
If size of patch text exceeds that limit - PatchContent splits it into per-file change
and shows changes for each selected file separately.
Otherwise - no changes, will be shown entire patch content.

src/common.h

@@ -213,6 +213,7 @@ namespace QGit {
 	extern const QString ACT_GROUP_KEY;
 	extern const QString ACT_TEXT_KEY;
 	extern const QString ACT_FLAGS_KEY;
+	extern const QString MAX_PATCH_KEY;
 
 	// settings default values
 	extern const QString CMT_TEMPL_DEF;

src/namespace_def.cpp

@@ -174,6 +174,7 @@ const QString QGit::FLAGS_KEY       = "flags";
 const QString QGit::PATCH_DIR_KEY   = "Patch/last_dir";
 const QString QGit::FMT_P_OPT_KEY   = "Patch/args";
 const QString QGit::AM_P_OPT_KEY    = "Patch/args_2";
+const QString QGit::MAX_PATCH_KEY   = "max_patch_size_show_complete";
 const QString QGit::EX_KEY          = "Working_dir/exclude_file_path";
 const QString QGit::EX_PER_DIR_KEY  = "Working_dir/exclude_per_directory_file_name";
 const QString QGit::CON_GEOM_KEY    = "Console/geometry";

src/patchcontent.cpp

@@ -6,6 +6,8 @@
 */
 #include <QScrollBar>
 #include <QTextCharFormat>
+#include <QTextStream>
+#include <QSettings>
 #include "common.h"
 #include "domain.h"
 #include "git.h"
@@ -117,6 +119,8 @@ void PatchContent::clear() {
 	matches.clear();
 	diffLoaded = false;
 	seekTarget = !target.isEmpty();
+	patchByFile.clear();
+	patchStats.clear();
 }
 
 void PatchContent::refresh() {
@@ -188,6 +192,14 @@ void PatchContent::centerOnFileHeader(StateInfo& st) {
 	target = st.fileName();
 	bool combined = (st.isMerge() && !st.allMergeFiles());
 	git->formatPatchFileHeader(&target, st.sha(), st.diffToSha(), combined, st.allMergeFiles());
+
+	auto it = patchByFile.constFind(target);
+	if (it != patchByFile.constEnd()) {
+		// If target is in the mapping
+		// then show per-file changesets.
+		setPlainText(it.value());
+	}
+
 	seekTarget = !target.isEmpty();
 	if (seekTarget)
 		seekTarget = !centerTarget(target);
@@ -215,6 +227,20 @@ void PatchContent::typeWriterFontChanged() {
 	setPlainText(toPlainText());
 }
 
+void PatchContent::parseDiff(const QString &data) {
+
+	static const QString delim = "diff --";
+	QStringList lst = data.split("\n" + delim, QString::SkipEmptyParts);
+
+	patchStats = lst.takeFirst();
+
+	for (auto& item : lst) {
+		QString file_diff = delim + item;
+		QString first_line = QTextStream(&file_diff).readLine();
+		patchByFile[first_line] = file_diff;
+	}
+}
+
 void PatchContent::processData(const QByteArray& fileChunk, int* prevLineNum) {
 
 	QString newLines;
@@ -286,7 +312,18 @@ void PatchContent::processData(const QByteArray& fileChunk, int* prevLineNum) {
 
 	if (prevLineNum || document()->isEmpty()) { // use the faster setPlainText()
 
-		setPlainText(newLines);
+		QSettings settings;
+		if (double(newLines.size()) / (1024*1024) > settings.value(QGit::MAX_PATCH_KEY).toDouble()) {
+			// If patch size exceeds the limit
+			// editor will show changes for individual files.
+			parseDiff(newLines);
+			setPlainText(patchStats);
+		} else {
+			// If patch size fits the limit
+			// editor will show complete patch.
+			setPlainText(newLines);
+		}
+
 		moveCursor(QTextCursor::Start);
 	} else {
 		int topLine = cursorForPosition(QPoint(1, 1)).blockNumber();

src/patchcontent.h

@@ -11,6 +11,7 @@
 #include <QTextEdit>
 #include <QSyntaxHighlighter>
 #include "common.h"
+#include <QHash>
 
 class Domain;
 class Git;
@@ -63,6 +64,7 @@ public slots:
 	void centerMatch(int id = 0);
 	bool centerTarget(SCRef target);
 	void processData(const QByteArray& data, int* prevLineNum = NULL);
+	void parseDiff(const QString& data);
 
 	Git* git;
 	DiffHighlighter* diffHighlighter;
@@ -75,6 +77,14 @@ public slots:
 	QString target;
 	bool seekTarget;
 
+	// Mapping of first string of file changeset ("diff --git a/... b/...")
+	// to complete file changeset;
+	// empty if size of patch less than maxPatchSizeShowComplete.
+	QHash<QString, QString> patchByFile;
+	// First section of patch text with changes stats;
+	// empty if size of patch less than maxPatchSizeShowComplete.
+	QString patchStats;
+
 	struct MatchSelection {
 		int paraFrom;
 		int indexFrom;

src/settings.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>513</width>
-    <height>377</height>
+    <height>416</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -576,6 +576,27 @@
                 </property>
                </widget>
               </item>
+              <item>
+               <layout class="QHBoxLayout" name="horizontalLayout_3">
+                <item>
+                 <widget class="QLabel" name="textLabelMaxPatchSize">
+                  <property name="text">
+                   <string>Max patch size MiB</string>
+                  </property>
+                  <property name="textFormat">
+                   <enum>Qt::PlainText</enum>
+                  </property>
+                 </widget>
+                </item>
+                <item>
+                 <widget class="QDoubleSpinBox" name="doubleSpinBoxMaxPatchSize">
+                  <property name="toolTip">
+                   <string>Bigger patches will be shown by-file</string>
+                  </property>
+                 </widget>
+                </item>
+               </layout>
+              </item>
              </layout>
             </item>
            </layout>
@@ -1683,6 +1704,22 @@
     </hint>
    </hints>
   </connection>
+  <connection>
+   <sender>doubleSpinBoxMaxPatchSize</sender>
+   <signal>valueChanged(double)</signal>
+   <receiver>settingsBase</receiver>
+   <slot>doubleSpinBoxMaxPatchSize_valueChanged(double)</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>20</x>
+     <y>20</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>20</x>
+     <y>20</y>
+    </hint>
+   </hints>
+  </connection>
   <connection>
    <sender>comboBoxGitConfigSource</sender>
    <signal>activated(int)</signal>

src/settingsimpl.cpp

@@ -66,6 +66,7 @@ SettingsImpl::SettingsImpl(QWidget* p, Git* g, int defTab) : QDialog(p), git(g)
 	SCRef exPDir(set.value(EX_PER_DIR_KEY, EX_PER_DIR_DEF).toString());
 	SCRef tmplt(set.value(CMT_TEMPL_KEY, CMT_TEMPL_DEF).toString());
 	SCRef CMArgs(set.value(CMT_ARGS_KEY).toString());
+	double MPOpt(set.value(MAX_PATCH_KEY).toDouble());
 
 	lineEditApplyPatchExtraOptions->setText(APOpt);
 	lineEditFormatPatchExtraOptions->setText(FPOpt);
@@ -77,6 +78,7 @@ SettingsImpl::SettingsImpl(QWidget* p, Git* g, int defTab) : QDialog(p), git(g)
 	lineEditCommitExtraOptions->setText(CMArgs);
 	lineEditTypeWriterFont->setText(TYPE_WRITER_FONT.toString());
 	lineEditTypeWriterFont->setCursorPosition(0); // font description could be long
+	doubleSpinBoxMaxPatchSize->setValue(MPOpt);
 
 	comboBoxDoubleClickAction->setCurrentIndex(set.value(DCLICK_ACT_KEY).toUInt());
 	setupCodecsCombo();
@@ -346,6 +348,11 @@ void SettingsImpl::lineEditExternalDiffViewer_textChanged(const QString& s) {
 	writeSetting(EXT_DIFF_KEY, s);
 }
 
+void SettingsImpl::doubleSpinBoxMaxPatchSize_valueChanged(double d) {
+
+	writeSetting(MAX_PATCH_KEY, d);
+}
+
 void SettingsImpl::lineEditExternalEditor_textChanged(const QString& s) {
 
 	writeSetting(EXT_EDITOR_KEY, s);

src/settingsimpl.h

@@ -44,6 +44,7 @@ protected slots:
 	void lineEditExcludePerDir_textChanged(const QString& s);
 	void lineEditTemplate_textChanged(const QString& s);
 	void lineEditCommitExtraOptions_textChanged(const QString& s);
+	void doubleSpinBoxMaxPatchSize_valueChanged(double d);
 	void comboBoxDoubleClickAction_activated(int i);
 	void comboBoxCodecs_activated(int i);
 	void comboBoxUserSrc_activated(int i);