api/buffer: introduce buffer_[gs]et_lines with new indexing convention.

-1 is index past the end, and -2 is the index of the last element.
This eliminates the need for include_start/include_end.

Allow the handling of out-of-bounds to be configurable.

1 files changed, 9 insertions, 6 deletions

diff --git a/test/functional/api/buffer_spec.lua b/test/functional/api/buffer_spec.lua
index c924988d06..1fab9125b9 100644
--- a/test/functional/api/buffer_spec.lua
+++ b/test/functional/api/buffer_spec.lua
@@ -35,10 +35,11 @@ describe('buffer_* functions', function()
       eq('', curbuf('get_line', 0))
     end)
 
-    it('get_line: out-of-bounds returns empty string', function()
+    it('get_line: out-of-bounds is an error', function()
       curbuf('set_line', 0, 'line1.a')
-      eq('', curbuf('get_line', 1))
-      eq('', curbuf('get_line', -2))
+      eq(1, curbuf('line_count')) -- sanity
+      eq(false, pcall(curbuf, 'get_line', 1))
+      eq(false, pcall(curbuf, 'get_line', -2))
     end)
 
     it('set_line, del_line: out-of-bounds is an error', function()
@@ -68,14 +69,16 @@ describe('buffer_* functions', function()
       eq({}, curbuf('get_line_slice', -4, -5, true, true))
     end)
 
-    it('set_line_slice: out-of-bounds is an error', function()
+    it('set_line_slice: out-of-bounds extends past end', function()
       curbuf('set_line_slice', 0, 0, true, true, {'a', 'b', 'c'})
       eq({'a', 'b', 'c'}, curbuf('get_line_slice', 0, 2, true, true)) --sanity
 
       eq({'c'}, curbuf('get_line_slice', -1, 4, true, true))
       eq({'a', 'b', 'c'}, curbuf('get_line_slice', 0, 5, true, true))
-      eq(false, pcall(curbuf, 'set_line_slice', 4, 5, true, true, {'d'}))
-      eq(false, pcall(curbuf, 'set_line_slice', -4, -5, true, true, {'d'}))
+      curbuf('set_line_slice', 4, 5, true, true, {'d'})
+      eq({'a', 'b', 'c', 'd'}, curbuf('get_line_slice', 0, 5, true, true))
+      curbuf('set_line_slice', -4, -5, true, true, {'e'})
+      eq({'e', 'a', 'b', 'c', 'd'}, curbuf('get_line_slice', 0, 5, true, true))
     end)
 
     it('works', function()