:matching-bracket, fix matching bracket highlighting in some cases

7 files changed, 60 insertions, 39 deletions

diff --git a/buffer.c b/buffer.c
index f607f10..5ecdf4f 100644
--- a/buffer.c
+++ b/buffer.c
@@ -177,30 +177,25 @@ bool buffer_unsaved_changes(TextBuffer *buffer) {
 char32_t buffer_char_at_pos(TextBuffer *buffer, BufferPos pos) {
 	if (!buffer_pos_valid(buffer, pos))
 		return 0;
-	
 	Line *line = &buffer->lines[pos.line];
+	if (pos.index >= line->len)
+		return 0;
 	return line->str[pos.index];
 }
 
 char32_t buffer_char_before_pos(TextBuffer *buffer, BufferPos pos) {
-	assert(buffer_pos_valid(buffer, pos));
+	if (!buffer_pos_valid(buffer, pos))
+		return 0;
 	if (pos.index == 0) return 0;
 	return buffer->lines[pos.line].str[pos.index - 1];
 }
 
-char32_t buffer_char_after_pos(TextBuffer *buffer, BufferPos pos) {
-	assert(buffer_pos_valid(buffer, pos));
-	Line *line = &buffer->lines[pos.line];
-	if (pos.index >= line->len) return 0;
-	return line->str[pos.index];
-}
-
 char32_t buffer_char_before_cursor(TextBuffer *buffer) {
 	return buffer_char_before_pos(buffer, buffer->cursor_pos);
 }
 
-char32_t buffer_char_after_cursor(TextBuffer *buffer) {
-	return buffer_char_after_pos(buffer, buffer->cursor_pos);
+char32_t buffer_char_at_cursor(TextBuffer *buffer) {
+	return buffer_char_at_pos(buffer, buffer->cursor_pos);
 }
 
 BufferPos buffer_pos_start_of_file(TextBuffer *buffer) {
@@ -1940,7 +1935,7 @@ bool buffer_change_number_at_pos(TextBuffer *buffer, BufferPos *ppos, i64 by) {
 	if (is32_alnum(buffer_char_before_pos(buffer, pos))) {
 		buffer_pos_move_left_words(buffer, &pos, 1);
 	}
-	char32_t c = buffer_char_after_pos(buffer, pos);
+	char32_t c = buffer_char_at_pos(buffer, pos);
 	if (c >= 127 || !isdigit((char)c)) {
 		if (c != '-') {
 			// not a number
@@ -2864,6 +2859,38 @@ bool buffer_handle_click(Ted *ted, TextBuffer *buffer, vec2 click, u8 times) {
 	return false;
 }
 
+bool buffer_pos_move_to_matching_bracket(TextBuffer *buffer, BufferPos *pos) {
+	Language language = buffer_language(buffer);
+	char32_t bracket_char = buffer_char_at_pos(buffer, *pos);
+	char32_t matching_char = syntax_matching_bracket(language, bracket_char);
+	if (bracket_char && matching_char) {
+		int direction = syntax_is_opening_bracket(language, bracket_char) ? +1 : -1;
+		int depth = 1;
+		while (buffer_pos_move_right(buffer, pos, direction)) {
+			char32_t c = buffer_char_at_pos(buffer, *pos);
+			if (c == bracket_char) depth += 1;
+			else if (c == matching_char) depth -= 1;
+			if (depth == 0) break;
+		}
+		return true;
+	} else {
+		return false;
+	}
+}
+
+bool buffer_cursor_move_to_matching_bracket(TextBuffer *buffer) {
+	// it's more natural here to consider the character to the left of the cursor
+	BufferPos pos = buffer->cursor_pos;
+	if (pos.index == 0) return false;
+	buffer_pos_move_left(buffer, &pos, 1);
+	if (buffer_pos_move_to_matching_bracket(buffer, &pos)) {
+		buffer_pos_move_right(buffer, &pos, 1);
+		buffer_cursor_move_to_pos(buffer, pos);
+		return true;
+	}
+	return false;
+}
+
 // Render the text buffer in the given rectangle
 void buffer_render(TextBuffer *buffer, Rect r) {
 	
@@ -3123,25 +3150,11 @@ void buffer_render(TextBuffer *buffer, Rect r) {
 	if (ted->active_buffer == buffer) {
 		
 		// highlight matching brackets
-		char32_t cursor_bracket = buffer_char_before_cursor(buffer);
-		char32_t matching_bracket = syntax_matching_bracket(language, cursor_bracket);
-		if (cursor_bracket && matching_bracket) {
-			int direction = syntax_is_opening_bracket(language, cursor_bracket) ? +1 : -1;
-			int depth = 1;
-			BufferPos pos = buffer->cursor_pos;
+		BufferPos pos = buffer->cursor_pos;
+		if (pos.index > 0) {
+			// it's more natural to consider the bracket to the left of the cursor
 			buffer_pos_move_left(buffer, &pos, 1);
-			while (pos.line >= start_line) {
-				if (buffer_pos_move_right(buffer, &pos, direction)) {
-					char32_t c = buffer_char_after_pos(buffer, pos);
-					if (c == cursor_bracket) depth += 1;
-					else if (c == matching_bracket) depth -= 1;
-					if (depth == 0) break;
-				} else {
-					break;
-				}
-			}
-			if (depth == 0) {
-				// highlight it
+			if (buffer_pos_move_to_matching_bracket(buffer, &pos)) {
 				vec2 gl_pos = buffer_pos_to_pixels(buffer, pos);
 				Rect hl_rect = rect(gl_pos, Vec2(char_width, char_height));
 				if (buffer_clip_rect(buffer, &hl_rect)) {
diff --git a/command.c b/command.c
index 5b3411b..fd75189 100644
--- a/command.c
+++ b/command.c
@@ -37,6 +37,7 @@ static CommandName command_names[] = {
 	{"select-all", CMD_SELECT_ALL},
 	{"select-up-blank-line", CMD_SELECT_UP_BLANK_LINE},
 	{"select-down-blank-line", CMD_SELECT_DOWN_BLANK_LINE},
+	{"matching-bracket", CMD_MATCHING_BRACKET},
 	{"clear-selection", CMD_CLEAR_SELECTION},
 	{"page-up", CMD_PAGE_UP},
 	{"page-down", CMD_PAGE_DOWN},
@@ -292,7 +293,10 @@ void command_execute_ex(Ted *ted, Command c, CommandArgument full_argument, Comm
 		if (buffer)
 			buffer_cursor_move_to_prev_pos(buffer);
 		break;
-	
+	case CMD_MATCHING_BRACKET:
+		if (buffer)
+			buffer_cursor_move_to_matching_bracket(buffer);
+		break;
 	case CMD_INSERT_TEXT: {
 		const char *str = argument_str;
 		if (str && buffer) {
diff --git a/command.h b/command.h
index 408bfbe..97a7c43 100644
--- a/command.h
+++ b/command.h
@@ -46,6 +46,8 @@ typedef enum {
 	CMD_END_OF_FILE,
 	/// go to previous position
 	CMD_PREVIOUS_POSITION,
+	/// move cursor to matching bracket
+	CMD_MATCHING_BRACKET,
 	CMD_SELECT_START_OF_FILE,
 	CMD_SELECT_END_OF_FILE,
 	/// select entire buffer
diff --git a/ide-autocomplete.c b/ide-autocomplete.c
index db9645c..3d5e24c 100644
--- a/ide-autocomplete.c
+++ b/ide-autocomplete.c
@@ -33,7 +33,7 @@ static bool autocomplete_should_display_phantom(Ted *ted) {
 		&& !buffer->is_line_buffer
 		&& buffer_settings(buffer)->phantom_completions
 		&& is32_word(buffer_char_before_cursor(buffer))
-		&& !is32_word(buffer_char_after_cursor(buffer));
+		&& !is32_word(buffer_char_at_cursor(buffer));
 	if (!show)
 		autocomplete_clear_phantom(ac);
 	return show;
diff --git a/main.c b/main.c
index e2c795b..64bf3ca 100644
--- a/main.c
+++ b/main.c
@@ -1,6 +1,4 @@
 /*
-TODO:
-- :go-to-matching-bracket
 FUTURE FEATURES:
 - highlight TODO, FIXME, XXX, others(?) in comments
 - autodetect indentation (tabs vs spaces)
diff --git a/ted.cfg b/ted.cfg
index 83662da..3b6909b 100644
--- a/ted.cfg
+++ b/ted.cfg
@@ -232,6 +232,8 @@ Ctrl+Shift+End = :select-end-of-file
 Ctrl+a = :select-all
 # go to previous cursor position
 Ctrl+p = :previous-position
+# move cursor to matching bracket
+Ctrl+Shift+5 = :matching-bracket
 # Ctrl+Shift+d = :clear-selection
 
 # insertion
diff --git a/ted.h b/ted.h
index de00472..bed54fe 100644
--- a/ted.h
+++ b/ted.h
@@ -917,20 +917,22 @@ void buffer_create(TextBuffer *buffer, Ted *ted);
 void line_buffer_create(TextBuffer *buffer, Ted *ted);
 /// does this buffer have unsaved changes?
 bool buffer_unsaved_changes(TextBuffer *buffer);
-/// returns the character at position pos, or 0 if pos is invalid
+/// returns the character after position pos, or 0 if pos is invalid
 char32_t buffer_char_at_pos(TextBuffer *buffer, BufferPos pos);
+/// returns the character after the cursor
+char32_t buffer_char_at_cursor(TextBuffer *buffer);
 /// returns the character before position pos, or 0 if pos is invalid or at the start of a line
 char32_t buffer_char_before_pos(TextBuffer *buffer, BufferPos pos);
-/// returns the character after position pos, or 0 if pos is invalid or at the end of a line
-char32_t buffer_char_after_pos(TextBuffer *buffer, BufferPos pos);
 /// returns the character to the left of the cursor, or 0 if the cursor at the start of the line.
 char32_t buffer_char_before_cursor(TextBuffer *buffer);
-/// returns the character to the right of the cursor, 0 if cursor is at end of line
-char32_t buffer_char_after_cursor(TextBuffer *buffer);
 /// buffer position of start of file
 BufferPos buffer_pos_start_of_file(TextBuffer *buffer);
 /// buffer position of end of file
 BufferPos buffer_pos_end_of_file(TextBuffer *buffer);
+/// move position to matching bracket. returns true if there was a bracket at the position, otherwise returns false and does nothing.
+bool buffer_pos_move_to_matching_bracket(TextBuffer *buffer, BufferPos *pos);
+/// move cursor to matching bracket. returns true if cursor was to the right of a bracket.
+bool buffer_cursor_move_to_matching_bracket(TextBuffer *buffer);
 /// ensures that `p` refers to a valid position, moving it if needed.
 void buffer_pos_validate(TextBuffer *buffer, BufferPos *p);
 /// is this a valid buffer position?