Implement explicit tab stops per line.

From Nick Gravgaard.

10 files changed, 290 insertions, 4 deletions

diff --git a/doc/ScintillaDoc.html b/doc/ScintillaDoc.html
index 9cc5cae18..689d9c949 100644
--- a/doc/ScintillaDoc.html
+++ b/doc/ScintillaDoc.html
@@ -3380,6 +3380,10 @@ struct Sci_TextToFind {
     syntax. Tabs are normally used in editors to insert a tab character or to pad text with spaces
     up to the next tab.</p>
 
+    <p>When Scintilla is laying out a section of text, text after a tab character will usually be
+    displayed at the next multiple of TABWIDTH columns from the left. However, it is also possible
+    to explicitly set tabstops in pixels for each line.</p>
+
     <p>Scintilla can be set to treat tab and backspace in the white space at the start of a line in
     a special way: inserting a tab indents the line to the next indent position rather than just
     inserting a tab at the current character position and backspace unindents the line rather than
@@ -3387,6 +3391,9 @@ struct Sci_TextToFind {
     you to generate code.</p>
     <code><a class="message" href="#SCI_SETTABWIDTH">SCI_SETTABWIDTH(int widthInChars)</a><br />
      <a class="message" href="#SCI_GETTABWIDTH">SCI_GETTABWIDTH</a><br />
+     <a class="message" href="#SCI_CLEARTABSTOPS">SCI_CLEARTABSTOPS(int line)</a><br />
+     <a class="message" href="#SCI_ADDTABSTOP">SCI_ADDTABSTOP(int line, int x)</a><br />
+     <a class="message" href="#SCI_GETNEXTTABSTOP">SCI_GETNEXTTABSTOP(int line, int x)</a><br />
      <a class="message" href="#SCI_SETUSETABS">SCI_SETUSETABS(bool useTabs)</a><br />
      <a class="message" href="#SCI_GETUSETABS">SCI_GETUSETABS</a><br />
      <a class="message" href="#SCI_SETINDENT">SCI_SETINDENT(int widthInChars)</a><br />
@@ -3413,6 +3420,14 @@ struct Sci_TextToFind {
     character in <code>STYLE_DEFAULT</code>. The default tab width is 8 characters. There are no
     limits on tab sizes, but values less than 1 or large values may have undesirable effects.</p>
 
+    <p><b id="SCI_CLEARTABSTOPS">SCI_CLEARTABSTOPS(int line)</b><br />
+     <b id="SCI_ADDTABSTOP">SCI_ADDTABSTOP(int line, int x)</b><br />
+     <b id="SCI_GETNEXTTABSTOP">SCI_GETNEXTTABSTOP(int line, int x)</b><br />
+     <code>SCI_CLEARTABSTOPS</code> clears explicit tabstops on a line. <code>SCI_ADDTABSTOP</code>
+    adds an explicit tabstop at the specified distance from the left (in pixels), and
+    <code>SCI_GETNEXTTABSTOP</code> gets the next explicit tabstop position, or zero if there
+    aren't any.</p>
+
     <p><b id="SCI_SETUSETABS">SCI_SETUSETABS(bool useTabs)</b><br />
      <b id="SCI_GETUSETABS">SCI_GETUSETABS</b><br />
      <code>SCI_SETUSETABS</code> determines whether indentation should be created out of a mixture
diff --git a/doc/ScintillaHistory.html b/doc/ScintillaHistory.html
index 6cefeab13..3bb58f509 100644
--- a/doc/ScintillaHistory.html
+++ b/doc/ScintillaHistory.html
@@ -452,6 +452,7 @@
 	<td>johnsonj</td>
       </tr><tr>
 	<td>Vicente</td>
+	<td>Nick Gravgaard</td>
     </tr>
     </table>
     <p>
@@ -483,6 +484,9 @@
 	<a href="http://sourceforge.net/p/scintilla/bugs/1532/">Bug #1532</a>.
 	</li>
 	<li>
+	Explicit tab stops may be set for each line.
+	</li>
+	<li>
 	On Windows, when using Korean input methods, IME composition is moved from a
 	separate window into the Scintilla window.
 	</li>
diff --git a/include/Scintilla.h b/include/Scintilla.h
index deb945c6a..949d42267 100644
--- a/include/Scintilla.h
+++ b/include/Scintilla.h
@@ -92,6 +92,9 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SCI_SETBUFFEREDDRAW 2035
 #define SCI_SETTABWIDTH 2036
 #define SCI_GETTABWIDTH 2121
+#define SCI_CLEARTABSTOPS 2675
+#define SCI_ADDTABSTOP 2676
+#define SCI_GETNEXTTABSTOP 2677
 #define SC_CP_UTF8 65001
 #define SCI_SETCODEPAGE 2037
 #define MARKER_MAX 31
@@ -957,7 +960,8 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SC_MOD_CONTAINER 0x40000
 #define SC_MOD_LEXERSTATE 0x80000
 #define SC_MOD_INSERTCHECK 0x100000
-#define SC_MODEVENTMASKALL 0x1FFFFF
+#define SC_MOD_CHANGETABSTOPS 0x200000
+#define SC_MODEVENTMASKALL 0x3FFFFF
 #define SC_UPDATE_CONTENT 0x1
 #define SC_UPDATE_SELECTION 0x2
 #define SC_UPDATE_V_SCROLL 0x4
diff --git a/include/Scintilla.iface b/include/Scintilla.iface
index cfbc7bc9f..b0399e5ee 100644
--- a/include/Scintilla.iface
+++ b/include/Scintilla.iface
@@ -226,6 +226,15 @@ set void SetTabWidth=2036(int tabWidth,)
 # Retrieve the visible size of a tab.
 get int GetTabWidth=2121(,)
 
+# Clear explicit tabstops on a line.
+fun void ClearTabStops=2675(int line,)
+
+# Add an explicit tab stop for a line.
+fun void AddTabStop=2676(int line, int x)
+
+# Find the next explicit tab stop position on a line after a position.
+fun int GetNextTabStop=2677(int line, int x)
+
 # The SC_CP_UTF8 value can be used to enter Unicode mode.
 # This is the same value as CP_UTF8 in Windows
 val SC_CP_UTF8=65001
@@ -2523,7 +2532,8 @@ val SC_MOD_CHANGEANNOTATION=0x20000
 val SC_MOD_CONTAINER=0x40000
 val SC_MOD_LEXERSTATE=0x80000
 val SC_MOD_INSERTCHECK=0x100000
-val SC_MODEVENTMASKALL=0x1FFFFF
+val SC_MOD_CHANGETABSTOPS=0x200000
+val SC_MODEVENTMASKALL=0x3FFFFF
 
 enu Update=SC_UPDATE_
 val SC_UPDATE_CONTENT=0x1
diff --git a/src/EditView.cxx b/src/EditView.cxx
index b033c7cf6..c46a0fbcf 100644
--- a/src/EditView.cxx
+++ b/src/EditView.cxx
@@ -29,6 +29,7 @@
 #include "RunStyles.h"
 #include "ContractionState.h"
 #include "CellBuffer.h"
+#include "PerLine.h"
 #include "KeyMap.h"
 #include "Indicator.h"
 #include "XPM.h"
@@ -170,6 +171,7 @@ void DrawStyledText(Surface *surface, const ViewStyle &vs, int styleOffset, PRec
 const XYPOSITION epsilon = 0.0001f;	// A small nudge to avoid floating point precision issues
 
 EditView::EditView() {
+	ldTabstops = NULL;
 	hideSelection = false;
 	drawOverstrikeCaret = true;
 	bufferedDraw = true;
@@ -185,6 +187,11 @@ EditView::EditView() {
 	posCache.SetSize(0x400);
 }
 
+EditView::~EditView() {
+	delete ldTabstops;
+	ldTabstops = NULL;
+}
+
 bool EditView::SetTwoPhaseDraw(bool twoPhaseDraw) {
 	const PhasesDraw phasesDrawNew = twoPhaseDraw ? phasesTwo : phasesOne;
 	const bool redraw = phasesDraw != phasesDrawNew;
@@ -203,6 +210,54 @@ bool EditView::LinesOverlap() const {
 	return phasesDraw == phasesMultiple;
 }
 
+void EditView::ClearAllTabstops() {
+	delete ldTabstops;
+	ldTabstops = 0;
+}
+
+int EditView::NextTabstopPos(int line, int x, int tabWidth) const {
+	int next = GetNextTabstop(line, x);
+	if (next > 0)
+		return next;
+	return ((((x + 2) / tabWidth) + 1) * tabWidth);
+}
+
+bool EditView::ClearTabstops(int line) {
+	LineTabstops *lt = static_cast<LineTabstops *>(ldTabstops);
+	return lt && lt->ClearTabstops(line);
+}
+
+bool EditView::AddTabstop(int line, int x) {
+	if (!ldTabstops) {
+		ldTabstops = new LineTabstops();
+	}
+	LineTabstops *lt = static_cast<LineTabstops *>(ldTabstops);
+	return lt && lt->AddTabstop(line, x);
+}
+
+int EditView::GetNextTabstop(int line, int x) const {
+	LineTabstops *lt = static_cast<LineTabstops *>(ldTabstops);
+	if (lt) {
+		return lt->GetNextTabstop(line, x);
+	} else {
+		return 0;
+	}
+}
+
+void EditView::LinesAddedOrRemoved(int lineOfPos, int linesAdded) {
+	if (ldTabstops) {
+		if (linesAdded > 0) {
+			for (int line = lineOfPos; line < lineOfPos + linesAdded; line++) {
+				ldTabstops->InsertLine(line);
+			}
+		} else {
+			for (int line = (lineOfPos + -linesAdded) - 1; line >= lineOfPos; line--) {
+				ldTabstops->RemoveLine(line);
+			}
+		}
+	}
+}
+
 void EditView::DropGraphics(bool freeObjects) {
 	if (freeObjects) {
 		delete pixmapLine;
@@ -397,8 +452,9 @@ void EditView::LayoutLine(const EditModel &model, int line, Surface *surface, co
 					XYPOSITION representationWidth = vstyle.controlCharWidth;
 					if (ll->chars[ts.start] == '\t') {
 						// Tab is a special case of representation, taking a variable amount of space
-						representationWidth =
-							((static_cast<int>((ll->positions[ts.start] + 2) / vstyle.tabWidth) + 1) * vstyle.tabWidth) - ll->positions[ts.start];
+						const int x = static_cast<int>(ll->positions[ts.start]);
+						const int tabWidth = static_cast<int>(vstyle.tabWidth);
+						representationWidth = static_cast<XYPOSITION>(NextTabstopPos(line, x, tabWidth) - ll->positions[ts.start]);
 					} else {
 						if (representationWidth <= 0.0) {
 							XYPOSITION positionsRepr[256];	// Should expand when needed
diff --git a/src/EditView.h b/src/EditView.h
index 7d64aff90..18451104f 100644
--- a/src/EditView.h
+++ b/src/EditView.h
@@ -48,6 +48,7 @@ void DrawStyledText(Surface *surface, const ViewStyle &vs, int styleOffset, PRec
 class EditView {
 public:
 	PrintParameters printParameters;
+	PerLine *ldTabstops;
 
 	bool hideSelection;
 	bool drawOverstrikeCaret;
@@ -78,11 +79,19 @@ public:
 	PositionCache posCache;
 
 	EditView();
+	virtual ~EditView();
 
 	bool SetTwoPhaseDraw(bool twoPhaseDraw);
 	bool SetPhasesDraw(int phases);
 	bool LinesOverlap() const;
 
+	void ClearAllTabstops();
+	int NextTabstopPos(int line, int x, int tabWidth) const;
+	bool ClearTabstops(int line);
+	bool AddTabstop(int line, int x);
+	int GetNextTabstop(int line, int x) const;
+	void LinesAddedOrRemoved(int lineOfPos, int linesAdded);
+
 	void DropGraphics(bool freeObjects);
 	void AllocateGraphics(const ViewStyle &vsDraw);
 	void RefreshPixMaps(Surface *surfaceWindow, WindowID wid, const ViewStyle &vsDraw);
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 7fb849114..1c1e38d65 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -29,6 +29,7 @@
 #include "RunStyles.h"
 #include "ContractionState.h"
 #include "CellBuffer.h"
+#include "PerLine.h"
 #include "KeyMap.h"
 #include "Indicator.h"
 #include "XPM.h"
@@ -1987,6 +1988,9 @@ void Editor::ClearAll() {
 			pdoc->MarginClearAll();
 		}
 	}
+
+	view.ClearAllTabstops();
+
 	sel.Clear();
 	SetTopLine(0);
 	SetVerticalScrollPos();
@@ -2457,6 +2461,9 @@ void Editor::NotifyModified(Document *, DocModification mh, void *) {
 			Redraw();
 		}
 	}
+	if (mh.modificationType & SC_MOD_CHANGETABSTOPS) {
+		Redraw();
+	}
 	if (mh.modificationType & SC_MOD_LEXERSTATE) {
 		if (paintState == painting) {
 			CheckForChangeOutsidePaint(
@@ -2520,6 +2527,7 @@ void Editor::NotifyModified(Document *, DocModification mh, void *) {
 			} else {
 				cs.DeleteLines(lineOfPos, -mh.linesAdded);
 			}
+			view.LinesAddedOrRemoved(lineOfPos, mh.linesAdded);
 		}
 		if (mh.modificationType & SC_MOD_CHANGEANNOTATION) {
 			int lineDoc = pdoc->LineFromPosition(mh.position);
@@ -4813,6 +4821,8 @@ void Editor::SetDocPointer(Document *document) {
 	view.llc.Deallocate();
 	NeedWrapping();
 
+	view.ClearAllTabstops();
+
 	pdoc->AddWatcher(this, 0);
 	SetScrollBars();
 	Redraw();
@@ -5983,6 +5993,23 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 	case SCI_GETTABWIDTH:
 		return pdoc->tabInChars;
 
+	case SCI_CLEARTABSTOPS:
+		if (view.ClearTabstops(static_cast<int>(wParam))) {
+			DocModification mh(SC_MOD_CHANGETABSTOPS, 0, 0, 0, 0, static_cast<int>(wParam));
+			NotifyModified(pdoc, mh, NULL);
+		}
+		break;
+
+	case SCI_ADDTABSTOP:
+		if (view.AddTabstop(static_cast<int>(wParam), static_cast<int>(lParam))) {
+			DocModification mh(SC_MOD_CHANGETABSTOPS, 0, 0, 0, 0, static_cast<int>(wParam));
+			NotifyModified(pdoc, mh, NULL);
+		}
+		break;
+
+	case SCI_GETNEXTTABSTOP:
+		return view.GetNextTabstop(static_cast<int>(wParam), static_cast<int>(lParam));
+
 	case SCI_SETINDENT:
 		pdoc->indentInChars = static_cast<int>(wParam);
 		if (pdoc->indentInChars != 0)
diff --git a/src/PerLine.cxx b/src/PerLine.cxx
index 8b0dbc44b..8fd96cbed 100644
--- a/src/PerLine.cxx
+++ b/src/PerLine.cxx
@@ -7,6 +7,7 @@
 
 #include <string.h>
 
+#include <vector>
 #include <algorithm>
 
 #include "Platform.h"
@@ -484,3 +485,72 @@ int LineAnnotation::Lines(int line) const {
 	else
 		return 0;
 }
+
+LineTabstops::~LineTabstops() {
+	Init();
+}
+
+void LineTabstops::Init() {
+	for (int line = 0; line < tabstops.Length(); line++) {
+		delete tabstops[line];
+	}
+	tabstops.DeleteAll();
+}
+
+void LineTabstops::InsertLine(int line) {
+	if (tabstops.Length()) {
+		tabstops.EnsureLength(line);
+		tabstops.Insert(line, 0);
+	}
+}
+
+void LineTabstops::RemoveLine(int line) {
+	if (tabstops.Length() > line) {
+		delete tabstops[line];
+		tabstops.Delete(line);
+	}
+}
+
+bool LineTabstops::ClearTabstops(int line) {
+	if (line < tabstops.Length()) {
+		TabstopList *tl = tabstops[line];
+		if (tl) {
+			tl->clear();
+			return true;
+		}
+	}
+	return false;
+}
+
+bool LineTabstops::AddTabstop(int line, int x) {
+	tabstops.EnsureLength(line + 1);
+	if (!tabstops[line]) {
+		tabstops[line] = new TabstopList();
+	}
+
+	TabstopList *tl = tabstops[line];
+	if (tl) {
+		// tabstop positions are kept in order - insert in the right place
+		std::vector<int>::iterator it = std::lower_bound(tl->begin(), tl->end(), x);
+		// don't insert duplicates
+		if (it == tl->end() || *it != x) {
+			tl->insert(it, x);
+			return true;
+		}
+	}
+	return false;
+}
+
+int LineTabstops::GetNextTabstop(int line, int x) const {
+	if (line < tabstops.Length()) {
+		TabstopList *tl = tabstops[line];
+		if (tl) {
+			for (size_t i = 0; i < tl->size(); i++) {
+				if ((*tl)[i] > x) {
+					return (*tl)[i];
+				}
+			}
+		}
+	}
+	return 0;
+}
diff --git a/src/PerLine.h b/src/PerLine.h
index 70d0023e4..4bf1c88fd 100644
--- a/src/PerLine.h
+++ b/src/PerLine.h
@@ -112,6 +112,23 @@ public:
 	int Lines(int line) const;
 };
 
+typedef std::vector<int> TabstopList;
+
+class LineTabstops : public PerLine {
+	SplitVector<TabstopList *> tabstops;
+public:
+	LineTabstops() {
+	}
+	virtual ~LineTabstops();
+	virtual void Init();
+	virtual void InsertLine(int line);
+	virtual void RemoveLine(int line);
+
+	bool ClearTabstops(int line);
+	bool AddTabstop(int line, int x);
+	int GetNextTabstop(int line, int x) const;
+};
+
 #ifdef SCI_NAMESPACE
 }
 #endif
diff --git a/test/simpleTests.py b/test/simpleTests.py
index 67299e661..590d288b8 100644
--- a/test/simpleTests.py
+++ b/test/simpleTests.py
@@ -2042,6 +2042,80 @@ class TestWordChars(unittest.TestCase):
 		data = self.ed.GetPunctuationChars(None)
 		self.assertCharSetsEqual(data, expected)
 
+class TestExplicitTabStops(unittest.TestCase):
+
+	def setUp(self):
+		self.xite = Xite.xiteFrame
+		self.ed = self.xite.ed
+		self.ed.ClearAll()
+		self.ed.EmptyUndoBuffer()
+		# 2 lines of 4 characters
+		self.t = b"fun(\nint)"
+		self.ed.AddText(len(self.t), self.t)
+
+	def testAddingAndClearing(self):
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 0)
+
+		# Add a tab stop at 7
+		self.ed.AddTabStop(0, 7)
+		# Check added
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 7)
+		# Check does not affect line 1
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 0)
+
+		# Add a tab stop at 18
+		self.ed.AddTabStop(0, 18)
+		# Check added
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 7)
+		self.assertEquals(self.ed.GetNextTabStop(0,7), 18)
+		# Check does not affect line 1
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(1,7), 0)
+
+		# Add a tab stop between others at 13
+		self.ed.AddTabStop(0, 13)
+		# Check added
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 7)
+		self.assertEquals(self.ed.GetNextTabStop(0,7), 13)
+		self.assertEquals(self.ed.GetNextTabStop(0,13), 18)
+		# Check does not affect line 1
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(1,7), 0)
+
+		self.ed.ClearTabStops(0)
+		# Check back to original state
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 0)
+
+	def testLineInsertionDeletion(self):
+		# Add a tab stop at 7 on line 1
+		self.ed.AddTabStop(1, 7)
+		# Check added
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 7)
+
+		# More text at end
+		self.ed.AddText(len(self.t), self.t)
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 7)
+		self.assertEquals(self.ed.GetNextTabStop(2,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(3,0), 0)
+
+		# Another 2 lines before explicit line moves the explicit tab stop
+		data = b"x\ny\n"
+		self.ed.InsertText(4, data)
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(2,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(3,0), 7)
+		self.assertEquals(self.ed.GetNextTabStop(4,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(5,0), 0)
+
+		# Undo moves the explicit tab stop back
+		self.ed.Undo()
+		self.assertEquals(self.ed.GetNextTabStop(0,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(1,0), 7)
+		self.assertEquals(self.ed.GetNextTabStop(2,0), 0)
+		self.assertEquals(self.ed.GetNextTabStop(3,0), 0)
+
 if __name__ == '__main__':
 	uu = Xite.main("simpleTests")
 	#~ for x in sorted(uu.keys()):