[PATCH] Disable bracketed paste mode in GDB tests

[Tom Tromey <tom@tromey.com>]

I have a patch to import GNU readline 8.1 into GDB.  However, when
running the tests, there were a number of failures due to "bracketed
paste mode".  This is a terminal feature that readline 8.1 enables by
default.

The simplest way to work around this was to always make a ".inputrc"
for GDB tests that will tell readline to disable brackted paste mode.

gdb/testsuite/ChangeLog
2021-01-18  Tom Tromey  <tom@tromey.com>

	* lib/gdb.exp (default_gdb_init): Set INPUTRC to a cached file.
---
 gdb/testsuite/ChangeLog   |  4 ++++
 gdb/testsuite/lib/gdb.exp | 13 ++++++-------
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index ae24fe2f49c..7b0420d8f00 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -5265,13 +5265,12 @@ proc default_gdb_init { test_file_name } {
     setenv LC_CTYPE C
     setenv LANG C
 
-    # Don't let a .inputrc file or an existing setting of INPUTRC mess up
-    # the test results.  Even if /dev/null doesn't exist on the particular
-    # platform, the readline library will use the default setting just by
-    # failing to open the file.  OTOH, opening /dev/null successfully will
-    # also result in the default settings being used since nothing will be
-    # read from this file.
-    setenv INPUTRC "/dev/null"
+    # Don't let a .inputrc file or an existing setting of INPUTRC mess
+    # up the test results.  Certain tests (style tests and TUI tests)
+    # want to set the terminal to a non-"dumb" value, and for those we
+    # want to disable bracketed paste mode.  It seems harmless to
+    # simply always do this.
+    setenv INPUTRC [cached_file inputrc "set enable-bracketed-paste off"]
 
     # This disables style output, which would interfere with many
     # tests.
-- 
2.26.2