BufferRange option syntax support <line>.<column>+<len> and is inclusive

Fixes #864

1 files changed, 17 insertions, 13 deletions

diff --git a/src/display_buffer.cc b/src/display_buffer.cc
index fdf3b1c4..4ac6a2fb 100644
--- a/src/display_buffer.cc
+++ b/src/display_buffer.cc
@@ -14,28 +14,32 @@ String option_to_string(BufferRange range)
 {
     return format("{}.{},{}.{}",
                   range.begin.line+1, range.begin.column+1,
-                  range.end.line+1, range.end.column+1);
+                  range.end.line, range.end.column);
 }
 
 void option_from_string(StringView str, BufferRange& opt)
 {
-    auto comma = find(str, ',');
-    auto dot_begin = find(StringView{str.begin(), comma}, '.');
-    auto dot_end = find(StringView{comma, str.end()}, '.');
+    auto sep = find_if(str, [](char c){ return c == ',' or c == '+'; });
+    auto dot_beg = find(StringView{str.begin(), sep}, '.');
+    auto dot_end = find(StringView{sep, str.end()}, '.');
 
-    if (comma == str.end() or dot_begin == comma or dot_end == str.end())
-        throw runtime_error(format("'{}' does not follow <line>.<column>,<line>.<column> format", str));
+    if (sep == str.end() or dot_beg == sep or
+        (*sep == ',' and dot_end == str.end()))
+        throw runtime_error(format("'{}' does not follow <line>.<column>,<line>.<column> or <line>.<column>+<len> format", str));
 
-    BufferCoord begin{str_to_int({str.begin(), dot_begin}) - 1,
-                    str_to_int({dot_begin+1, comma}) - 1};
+    const BufferCoord beg{str_to_int({str.begin(), dot_beg}) - 1,
+                          str_to_int({dot_beg+1, sep}) - 1};
 
-    BufferCoord end{str_to_int({comma+1, dot_end}) - 1,
-                  str_to_int({dot_end+1, str.end()}) - 1};
+    const bool len = (*sep == '+');
+    const BufferCoord end{len ? beg.line : str_to_int({sep+1, dot_end}) - 1,
+                          len ? beg.column + str_to_int({sep+1, str.end()})
+                              : str_to_int({dot_end+1, str.end()}) };
 
-    opt.begin = begin;
-    opt.end = end;
-}
+    if (beg.line < 0 or beg.column < 0 or end.line < 0 or end.column < 0)
+        throw runtime_error("coordinates elements should be >= 1");
 
+    opt = { beg, end };
+}
 
 StringView DisplayAtom::content() const
 {