Merge pull request #1431 from mitchellh/mouse-mods-alt

core: handle mouse capture events with link highlighting

src/Surface.zig

@@ -854,7 +854,7 @@ fn modsChanged(self: *Surface, mods: input.Mods) void {
         {
             self.renderer_state.mutex.lock();
             defer self.renderer_state.mutex.unlock();
-            self.renderer_state.mouse.mods = mods;
+            self.renderer_state.mouse.mods = self.mouseModsWithCapture(self.mouse.mods);
         }
 
         self.queueRender() catch |err| {
@@ -2372,6 +2372,9 @@ fn linkAtPos(
         break :mouse_pt viewport_point.toScreen(&self.io.terminal.screen);
     };
 
+    // Get our comparison mods
+    const mouse_mods = self.mouseModsWithCapture(self.mouse.mods);
+
     // Get the line we're hovering over.
     const line = self.io.terminal.screen.getLine(mouse_pt) orelse
         return null;
@@ -2382,7 +2385,7 @@ fn linkAtPos(
     for (self.config.links) |link| {
         switch (link.highlight) {
             .always, .hover => {},
-            .always_mods, .hover_mods => |v| if (!v.equal(self.mouse.mods)) continue,
+            .always_mods, .hover_mods => |v| if (!v.equal(mouse_mods)) continue,
         }
 
         var it = strmap.searchIterator(link.regex);
@@ -2398,6 +2401,25 @@ fn linkAtPos(
     return null;
 }
 
+/// This returns the mouse mods to consider for link highlighting or
+/// other purposes taking into account when shift is pressed for releasing
+/// the mouse from capture.
+///
+/// The renderer state mutex must be held.
+fn mouseModsWithCapture(self: *Surface, mods: input.Mods) input.Mods {
+    // In any of these scenarios, whatever mods are set (even shift)
+    // are preserved.
+    if (self.io.terminal.flags.mouse_event == .none) return mods;
+    if (!mods.shift) return mods;
+    if (self.mouseShiftCapture(false)) return mods;
+
+    // We have mouse capture, shift set, and we're not allowed to capture
+    // shift, so we can clear shift.
+    var final = mods;
+    final.shift = false;
+    return final;
+}
+
 /// Attempt to invoke the action of any link that is under the
 /// given position.
 ///

src/input/Link.zig

@@ -36,6 +36,11 @@ pub const Highlight = union(enum) {
     /// hovering or always. For always, all links will be highlighted
     /// when the mods are pressed regardless of if the mouse is hovering
     /// over them.
+    ///
+    /// Note that if "shift" is specified here, this will NEVER match in
+    /// TUI programs that capture mouse events. "Shift" with mouse capture
+    /// escapes the mouse capture but strips the "shift" so it can't be
+    /// detected.
     always_mods: Mods,
     hover_mods: Mods,
 };

src/renderer/Metal.zig

@@ -1551,12 +1551,12 @@ fn rebuildCells(
     const arena_alloc = arena.allocator();
 
     // Create our match set for the links.
-    var link_match_set = try self.config.links.matchSet(
+    var link_match_set: link.MatchSet = if (mouse.point) |mouse_pt| try self.config.links.matchSet(
         arena_alloc,
         screen,
-        mouse.point orelse .{},
+        mouse_pt,
         mouse.mods,
-    );
+    ) else .{};
 
     // Determine our x/y range for preedit. We don't want to render anything
     // here because we will render the preedit separately.

src/renderer/OpenGL.zig

@@ -987,12 +987,12 @@ pub fn rebuildCells(
     self.gl_cells_written = 0;
 
     // Create our match set for the links.
-    var link_match_set = try self.config.links.matchSet(
+    var link_match_set: link.MatchSet = if (mouse.point) |mouse_pt| try self.config.links.matchSet(
         arena_alloc,
         screen,
-        mouse.point orelse .{},
+        mouse_pt,
         mouse.mods,
-    );
+    ) else .{};
 
     // Determine our x/y range for preedit. We don't want to render anything
     // here because we will render the preedit separately.

src/renderer/link.zig

@@ -139,7 +139,7 @@ pub const MatchSet = struct {
     /// The matches.
     ///
     /// Important: this must be in left-to-right top-to-bottom order.
-    matches: []const terminal.Selection,
+    matches: []const terminal.Selection = &.{},
     i: usize = 0,
 
     pub fn deinit(self: *MatchSet, alloc: Allocator) void {