[PATCH] gdb/testsuite: fix completion tests when using READ1

[Bruno Larsen <blarsen@redhat.com>]

The commit a3da2e7e550c4fe79128b5e532dbb90df4d4f418 has introduced
regressions when testing using the READ1 mechanism. The reason for that
is the new failure path in proc test_gdb_complete_tab_unique, which
looks for GDB suggesting more than what the test inputted, but not the
correct answer, followed by a white space. Consider the following case:

int foo(int bar, int baz);

Sending the command "break foo<tab>" to GDB will return

break foo(int, int)

which easily fits the buffer in normal testing, so everything works, but
when reading one character at a time, the test will find the partial
"break foo(int, " and assume that there was a mistake, so we get a
spurious FAIL.

To fix these errors, this commit makes it so the relevant section is
only evaluated when the test is not being run with the READ1 mechanism.
---

With these changes, I only see a failure that was not introduced by my
original patch, when testing gdb.ada/complete.exp due to too much
output, I think.

---
 gdb/testsuite/lib/completion-support.exp | 30 +++++++++++++++++-------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/gdb/testsuite/lib/completion-support.exp b/gdb/testsuite/lib/completion-support.exp
index ea73c3bb367..9e76d7c9eb6 100644
--- a/gdb/testsuite/lib/completion-support.exp
+++ b/gdb/testsuite/lib/completion-support.exp
@@ -113,16 +113,28 @@ proc test_gdb_complete_tab_unique { input_line complete_line_re append_char_re }
     send_gdb "$input_line\t"
     set partial_complete [string_to_regexp $input_line]
     set res 1
-    gdb_test_multiple "" "$test" {
-	-re "^$complete_line_re$append_char_re$" {
-	    pass "$test"
-	}
-	-re "$partial_complete\[^ \]+ $" {
-	    fail "$test"
+    if { ![info exists ::env(READ1)] || $::env(READ1) == ""} {
+	gdb_test_multiple "" "$test" {
+	    -re "^$complete_line_re$append_char_re$" {
+		pass "$test"
+	    }
+	    -re "$partial_complete\[^ \]+ $" {
+		fail "$test"
+	    }
+	    timeout {
+		fail "$test (timeout)"
+		set res -1
+	    }
 	}
-	timeout {
-	    fail "$test (timeout)"
-	    set res -1
+    } else {
+	gdb_test_multiple "" "$test" {
+	    -re "^$complete_line_re$append_char_re$" {
+		pass "$test"
+	    }
+	    timeout {
+		fail "$test (timeout)"
+		set res -1
+	    }
 	}
     }
 
-- 
2.41.0