[PATCH 15/29] gdb/testsuite: Remove duplicates from gdb.base/complete-empty.exp

[Lancelot SIX via Gdb-patches <gdb-patches@sourceware.org>]

When I run the testsuite, I have:

    Running .../gdb/testsuite/gdb.base/complete-empty.exp ...
    DUPLICATE: gdb.base/complete-empty.exp: empty-input-line: cmd complete ""

This comes from how test_gdb_complete_unique works (more specifically,
how test_gdb_complete_unique_re works).  In this proc we can see:

    # Trim INPUT_LINE and COMPLETE LINE, for the case we're completing
    # a command with leading whitespace.  Leading command whitespace
    # is discarded by GDB.
    set input_line [string trimleft $input_line]
    set expected_output_re [string trimleft $complete_line_re]

This test is trying to test how a buffer containing no commands is
completed.  A buffer containing no command can be an empty buffer (first
scenario tested) or a buffer containing only white spaces.

Given the behavior of the test procedure described above (required
because the 'complete' command will trim anyway), our second test
(buffer containing only white spaces) is turned into the first test case
(empty buffer), leading to the DUPLICATE warning.

I see two options to solve this:

  1) Only test the tab-based completion for the test case with leading
     white spaces.
  2) Run the test with a prefix the second time we test an empty buffer,
     so it is registered under a different name.

I went for the first option which seems cleaner.

Tested on x86_64-linux.
---
 gdb/testsuite/gdb.base/complete-empty.exp | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/gdb/testsuite/gdb.base/complete-empty.exp b/gdb/testsuite/gdb.base/complete-empty.exp
index 4620ec2adc9..60f8e3f1a9e 100644
--- a/gdb/testsuite/gdb.base/complete-empty.exp
+++ b/gdb/testsuite/gdb.base/complete-empty.exp
@@ -42,7 +42,17 @@ proc_with_prefix empty-input-line {} {
     test_gdb_complete_unique "" "!" " " 1
 
     # Same, but with some leading whitespace.
-    test_gdb_complete_unique "   " "   !" " " 1
+
+    # This scenario is only tested using tab-completion and not the 'complete'
+    # command (as test_gdb_complete_tab_unique would do).  This is due to the
+    # fact that GDB will in fine trim its input (producing a trimmed output).
+    # Knowing that the testing framework trims the input and expected output,
+    # turning this test case into the one we just did above.
+    if { [readline_is_used] } {
+	if { [test_gdb_complete_tab_unique "   " "   !" " "] == -1 } {
+	    return -1
+	}
+    }
 }
 
 proc test_driver {} {
-- 
2.33.1