Merge branch 'topic/gs.541.format_new_buffer' into 'master'

Fix Buffer corruption during textEdit

Closes #541

See merge request eng/ide/gnatstudio!875

Author: AdrienBoulanger

lsp_client/src/gps-lsp_client-edit_workspace.adb

@@ -180,19 +180,19 @@ package body GPS.LSP_Client.Edit_Workspace is
             To         : constant GPS.Editors.Editor_Location'Class :=
               GPS.LSP_Client.Utilities.LSP_Position_To_Location
                 (Editor, Span.last);
-            Span_Text  : constant VSS.Strings.Virtual_String :=
-              Editor.Get_Text
-                (From                 => From,
-                 To                   => To,
-                 Include_Hidden_Chars => False);
+            --  We are using Get_Text below which includes the character after
+            --  To. TextEdits should ignore this character so move To backward
+            --  now to compensate.
+            --  Also handle the special case where From = To, we should not
+            --  move To backward or we will get the characters between From - 1
+            --  and To + 1.
             Old_Text   : constant VSS.Strings.Virtual_String :=
-              Span_Text.Head_Before (Span_Text.At_Last_Character);
-            --  XXX It is not clear why last character is ignored here. There
-            --  are two incorrect things might be here:
-            --   - remove LF character (CRLF must be handled too)
-            --   - conversion of LSP range is not equivalent to conversion of
-            --     two LSP positions
-            --  Need to be investigated!
+              (if From = To
+               then VSS.Strings.Empty_Virtual_String
+               else Editor.Get_Text
+                (From                 => From,
+                 To                   => To.Forward_Char (-1),
+                 Include_Hidden_Chars => False));
             New_Text   : constant VSS.Strings.Virtual_String :=
               Vectors.Element (C).Text;
 

testsuite/tests/gs.541.format_new_buffer/default.gpr

@@ -0,0 +1,3 @@
+project Default is
+
+end Default;

testsuite/tests/gs.541.format_new_buffer/test.py

@@ -0,0 +1,43 @@
+"""
+Create a new buffer and try to format it
+"""
+
+import GPS
+from gs_utils.internal.utils import (
+    run_test_driver,
+    wait_idle,
+    gps_assert,
+    wait_language_server,
+    timeout,
+)
+
+INIT_TEXT = """procedure Main is
+begin
+null;
+end Main;"""
+
+EXPECTED_TEXT = """procedure Main is
+begin
+   null;
+end Main;"""
+
+
+@run_test_driver
+def driver():
+    # Use GNATFormat LSP backend
+    GPS.Preference("LSP-Ada-Use-GNATformat").set(True)
+    GPS.Preference("Editor-Range-Formatter").set("LSP")
+    b = GPS.EditorBuffer.get(GPS.File("main.adb"))
+    yield wait_idle()
+    b.insert(b.at(1, 1), INIT_TEXT)
+    b.select(b.at(0, 0), b.at(4, 9))
+    yield timeout(5000)
+
+    # Format the second line in the aggregate
+    GPS.execute_action("format selection")
+    yield wait_language_server("textDocument/rangeFormatting")
+    yield wait_idle()
+
+    gps_assert(
+        b.get_chars(), EXPECTED_TEXT, "Wrong formatting"
+    )

testsuite/tests/gs.541.format_new_buffer/test.yaml

@@ -0,0 +1 @@
+title: 'gs.541.format_new_buffer'