[llvm-strings] Improve testing of llvm-strings

[jhenderson]

Summary

This patch attempts to tidy up the llvm-strings testing by:

1. Adding comments to every test.
2. Getting rid of canned input files, and have the tests generate them on the fly (this makes the tests self-contained).
3. Adding missing test coverage.
4. Renaming some tests that weren't clear as to their purpose.
5. Adding extra checking of various cases, formatting etc.
6. Removing a test that didn't seem to have any useful purpose for testing llvm-strings.

[rupprecht]

Just one test that needs fixing, LGTM otherwise:

test/tools/llvm-strings/version.test

4 ↗

(On Diff #214381)

This is actually testing the default cmake config; see this comment from llvm/test/tools/llvm-readobj/basic.test:

# Test version switch.
RUN: llvm-readobj --version | FileCheck %s --check-prefix=VERSION
RUN: llvm-readelf --version | FileCheck %s --check-prefix=VERSION
# In default configuration we could match "LLVM version", but the "LLVM" part
# can be changed with PACKAGE_NAME in CMake, so we match only version.
VERSION: version

[grimar]

test/tools/llvm-strings/all-sections.test

1 ↗

(On Diff #214381)

Should we use ## in this tests too? I would do this, since it is probably
not bad to have a single style across the all LLVM tests.

test/tools/llvm-strings/eof-no-string.test

2 ↗

(On Diff #214381)

I think it just does not print all strings that are shorter than 4 bytes?
I.e. not only the last line.

test/tools/llvm-strings/eof.test

5 ↗

(On Diff #214381)

What about combining this and eof-no-string.test test into one?

test/tools/llvm-strings/file-filename.test

10 ↗

(On Diff #214381)

My emotion for this test at first was: "what about multiple inputs?". Then I found
multiple-inputs.test test below. I would just inline it here.

test/tools/llvm-strings/help.test

12 ↗

(On Diff #214381)

Note: I am not sure why "Options" is in upper case when "Generic", but lower case when "General",
but my concern is that it makes the test case to be potentially brittle probably:

If you have --implicit-check-not="Generic Options:", then if somebody deside to change "Option"->"option",
then you'll get a broken test case. Not sure if we should think about this scenario in that way though.

test/tools/llvm-strings/length.test

13 ↗

(On Diff #214381)

What if -n 6 or -n -1 or -n foo?

test/tools/llvm-strings/version.test

1 ↗

(On Diff #214381)

I.d probably just put this into help.test. What do you think?

[jhenderson]

test/tools/llvm-strings/all-sections.test

1 ↗

(On Diff #214381)

I didn't bother here because this isn't used as an input to anything, but I can do so if you're bothered. Should I add '#' to the RUN and CHECK lines too? I'd prefer not to, mostly because that will unnecessarily make git blame less useful.

test/tools/llvm-strings/eof-no-string.test

1 ↗

(On Diff #214381)

I'm not sure why my patch isn't showing this, but this has been renamed from "terminator-neg.test".

2 ↗

(On Diff #214381)

Right, but this is specifically about the last line case (there are other cases for the general behaviour). A basic implementation would look something like:

const char *S = nullptr;
for (const char *P = Str.begin(); P != Str.end(); ++P) {
  if (!isPrint(P)) {
    if (P - S >= 4)
      printStr(S, P);
    S = nullptr;
  }
}

This wouldn't print the trailing characters at all. A naive fix would add the following after the loop:

if (S != nullptr)
  printStr(S, Str.end());

When the check should actually be if (S != nullptr && Str.end() - S >= 4). So this test case is checking that second clause in the final if.

Note that this and the original eof.test were written to fix a bug where that final if was missing.

test/tools/llvm-strings/eof.test

1 ↗

(On Diff #214381)

I'm not sure why my patch isn't showing this, but this has been renamed from "terminator.test".

5 ↗

(On Diff #214381)

I could do that, but I kept them separate because that's how they were previously. If you'd like me to fold them together, I can do so.

test/tools/llvm-strings/file-filename.test

10 ↗

(On Diff #214381)

Okay.

test/tools/llvm-strings/help.test

12 ↗

(On Diff #214381)

I agree that the inconsistent case is bad. I'm not sure of a good alternative (apart from making it a regex pattern of [Oo]). I'll give it a bit more thought.

test/tools/llvm-strings/length.test

13 ↗

(On Diff #214381)

-n -1 is actually broken. It looks like the command-line parser converts it to an unsigned, resulting in it being the equivalent of UINT_MAX. As GNU strings allows -1 as an alias for -n 1, we probably don't want to try to address this immediately, and fix that issue first, then see if the problem is still possible afterwards.

I'll add -n foo and -n 6 cases.

test/tools/llvm-strings/version.test

1 ↗

(On Diff #214381)

I prefer to keep each switch to a separate test, unless they're intricately linked (in this case --help and --version are not really linked).

4 ↗

(On Diff #214381)

Thanks! I'll fix that.

[jhenderson]

test/tools/llvm-strings/file-filename.test

10 ↗

(On Diff #214381)

Actually, multiple-inputs.test isn't just about the --print-file-name switch. It's more generally about how llvm-strings works with multiple inputs, i.e. it reads each of them in turn, and produces correct output with --print-filename and --radix when switching between files, so I think it belongs as a separate test.

Possibly I could be persuaded that the --print-file-name and --radix checks for multiple inputs belong in their respective tests, but I think multiple inputs still need testing separately.

[grimar]

test/tools/llvm-strings/all-sections.test

1 ↗

(On Diff #214381)

I'd use '##' fo comments, I agree it is probably no need to use them for RUN/CHECK lines.

test/tools/llvm-strings/eof.test

5 ↗

(On Diff #214381)

Phab did not show the renaming, so I assumed this is the new file.
Since it is not, it is OK to leave it as is in this patch I think.

(I would fold them in a followup though).

[jhenderson]

Addressed review comments:

• Made comments use double hash.
• Made some tests less brittle.
• Added extra test cases as suggested.

test/tools/llvm-strings/help.test

12 ↗

(On Diff #214381)

I've tried making it less likely to get missed, by putting the -NOT checks out-of-line, so that they're next to the positive checks. If the case is changed, hopefully the person updating the test will change both positive and negative cases.

test/tools/llvm-strings/length.test

13 ↗

(On Diff #214381)

-n -1 is actually broken. It looks like the command-line parser converts it to an unsigned

Turns out it's an int in the parser, so the parser accepts it, but it is then static_cast to a size_t! Anyway, still broken, and I've filed a bug for negative arguments.

[grimar]

LGTM.

[jhenderson]

test/tools/llvm-strings/stdin.test

11 ↗

(On Diff #214596)

On my Linux box, "echo -e" doesn't work without quoting the string to be echoed, so I did that throughout this test.

llvm/trunk/test/tools/llvm-strings/Inputs/abcd

-abcd
 

llvm/trunk/test/tools/llvm-strings/Inputs/numbers

-one
-two
-three
-four
-five
-six
-seven
-eight
-nine
-ten

llvm/trunk/test/tools/llvm-strings/Inputs/variable-length

-a
-ab
-abc
-abcd

llvm/trunk/test/tools/llvm-strings/all-sections.test

-RUN: llvm-strings -a %S/Inputs/abcd | FileCheck %s
-RUN: llvm-strings --all %S/Inputs/abcd | FileCheck %s
+## Show that the -a/--all switch is accepted. GNU strings checks specific object
+## file sections unless --all is specified. llvm-strings just looks at the entire
+## file, so this option is silently ignored.
+
+RUN: echo abcd | llvm-strings -a | FileCheck %s
+RUN: echo abcd | llvm-strings --all | FileCheck %s
 CHECK: abcd

llvm/trunk/test/tools/llvm-strings/archive-filename.test

+## Show that --print-file-name prints just the archive name for an archive and
+## not the member names.
+
 RUN: rm -rf %t && mkdir -p %t
-RUN: llvm-ar --format=gnu crs %t/archive.a %S/Inputs/abcd
+RUN: echo -n abcd > %t/abcd
+RUN: llvm-ar --format=gnu crs %t/archive.a %t/abcd
 RUN: llvm-strings -f %t/archive.a | FileCheck %s
 RUN: llvm-strings --print-file-name %t/archive.a | FileCheck %s
 
 CHECK: archive.a: !<arch>
 CHECK: archive.a: abcd/           0           0     0     644     4         `
 CHECK: archive.a: abcd
-

llvm/trunk/test/tools/llvm-strings/eof-no-string.test

+## Show that llvm-strings does not print the last string in the input if it is
+## too short and no unprintable character follows it.
+
+RUN: echo -n abc | llvm-strings - | FileCheck --allow-empty %s
+CHECK-NOT: abc

llvm/trunk/test/tools/llvm-strings/eof.test

+## Show that llvm-strings prints the last string in the input even if no
+## unprintable character follows it.
+
+RUN: echo -n abcdefg | llvm-strings - | FileCheck %s
+CHECK: abcdefg

llvm/trunk/test/tools/llvm-strings/file-filename.test

-RUN: llvm-strings -f %S/Inputs/abcd | FileCheck %s
-RUN: llvm-strings --print-file-name %S/Inputs/abcd | FileCheck %s --strict-whitespace
-CHECK: {{[\\/]}}abcd: abcd
+## Show that --print-file-name prints the name of the file before each line in
+## the output.
+
+RUN: echo abcd > %t
+RUN: echo efg >> %t
+RUN: echo hijk >> %t
+RUN: llvm-strings -f %t | FileCheck %s --strict-whitespace -DFILE=%t
+RUN: llvm-strings --print-file-name %t | FileCheck %s --strict-whitespace -DFILE=%t
+CHECK:      [[FILE]]: abcd
+CHECK-NEXT: [[FILE]]: hijk

llvm/trunk/test/tools/llvm-strings/help.test

-RUN: llvm-strings -h | FileCheck %s
-RUN: llvm-strings --help | FileCheck %s
+## Show that help text is printed correctly when requested.
+
+RUN: llvm-strings -h | FileCheck %s --check-prefixes=CHECK,CATEG
+RUN: llvm-strings --help | FileCheck %s --check-prefixes=CHECK,CATEG
+RUN: llvm-strings --help-list \
+RUN:   | FileCheck %s --check-prefixes=CHECK,LIST
 
 CHECK: OVERVIEW: llvm string dumper
 CHECK: USAGE: llvm-strings{{(.exe)?}} [options] <input object files>{{$}}
 CHECK: OPTIONS:
+CATEG:    General options:
+LIST-NOT: General options:
+CATEG:    Generic Options:
+LIST-NOT: Generic Options:
 CHECK: @FILE

llvm/trunk/test/tools/llvm-strings/length.test

-RUN: not llvm-strings -n 0 2>&1 %S/Inputs/variable-length | FileCheck --check-prefix CHECK-0 %s
-RUN: llvm-strings -n 1 %S/Inputs/variable-length | FileCheck --check-prefix CHECK-1 %s
-RUN: llvm-strings -n 2 %S/Inputs/variable-length | FileCheck --check-prefix CHECK-2 %s
-RUN: llvm-strings %S/Inputs/variable-length | FileCheck --check-prefix CHECK-DEFAULT %s
-
-STDIN: a
-STDIN: ab
-STDIN: abc
-STDIN: abcd
+## Show that llvm-strings prints only strings with length of at least the
+## requested number of bytes.
 
-CHECK-DEFAULT: abcd
+RUN: echo a > %t
+RUN: echo ab >> %t
+RUN: echo abc >> %t
+RUN: echo abcd >> %t
+RUN: echo abcde >> %t
+RUN: not llvm-strings -n 0 2>&1 %t | FileCheck --check-prefix CHECK-0 %s
+RUN: llvm-strings -n 1 %t | FileCheck --check-prefix CHECK-1 %s --implicit-check-not={{.}}
+RUN: llvm-strings -n 2 %t | FileCheck --check-prefix CHECK-2 %s --implicit-check-not={{.}}
+RUN: llvm-strings -n 4 %t | FileCheck --check-prefix CHECK-4 %s --implicit-check-not={{.}}
+RUN: llvm-strings -n 5 %t | FileCheck --check-prefix CHECK-5 %s --implicit-check-not={{.}}
+RUN: llvm-strings -n 6 %t | FileCheck %s --implicit-check-not={{.}} --allow-empty
+
+## Default is equivalent to -n 4.
+RUN: llvm-strings %t | FileCheck --check-prefix CHECK-4 %s --implicit-check-not={{.}}
+
+## Show --bytes works too.
+RUN: llvm-strings --bytes 2 %t | FileCheck --check-prefix CHECK-2 %s --implicit-check-not={{.}}
+
+## Show different syntaxes work.
+RUN: llvm-strings --bytes=2 %t | FileCheck --check-prefix CHECK-2 %s --implicit-check-not={{.}}
+RUN: llvm-strings -n=2 %t | FileCheck --check-prefix CHECK-2 %s --implicit-check-not={{.}}
 
 CHECK-0: invalid minimum string length 0
 
-CHECK-1: a
-CHECK-1: ab
-CHECK-1: abc
-CHECK-1: abcd
+CHECK-1:      a
+CHECK-1-NEXT: ab
+CHECK-1-NEXT: abc
+CHECK-1-NEXT: abcd
+CHECK-1-NEXT: abcde
 
-CHECK-2-NOT: a
-CHECK-2: ab
-CHECK-2: abc
-CHECK-2: abcd
-
+CHECK-2:      ab
+CHECK-2-NEXT: abc
+CHECK-2-NEXT: abcd
+CHECK-2-NEXT: abcde
+
+CHECK-4:      abcd
+CHECK-4-NEXT: abcde
+
+CHECK-5:      abcde
+
+## Show that a non-numeric argument is rejected.
+RUN: not llvm-strings -n foo %t 2>&1 | FileCheck %s --check-prefix=ERR
+ERR: llvm-strings{{.*}}: for the --bytes option: 'foo' value invalid for integer argument!

llvm/trunk/test/tools/llvm-strings/multiple-inputs.test

+## Show that llvm-strings reads every file specified on the command-line.
+## This test uses --print-file-name and --radix to show that the values are
+## updated for the second file.
+
+RUN: echo abcd > %t1
+RUN: echo 1234 >> %t1
+RUN: echo defg > %t2
+RUN: llvm-strings --print-file-name --radix=d %t1 %t2 \
+RUN:   | FileCheck %s -DFILE1=%t1 -DFILE2=%t2 --implicit-check-not={{.}}
+
+CHECK:      [[FILE1]]: 0 abcd
+CHECK-NEXT: [[FILE1]]: 5 1234
+CHECK-NEXT: [[FILE2]]: 0 defg

llvm/trunk/test/tools/llvm-strings/negative-char.test

+## Show that llvm-strings can handle a negative signed char value (i.e. > 0x7f).
+## Such characters should form string delimiters like other unprintable ones.
+
 # RUN: echo -e "z\0\x80\0a\0" | llvm-strings --bytes 1 - | FileCheck %s
 # CHECK: z{{$}}
 # CHECK-NEXT: {{^}}a

llvm/trunk/test/tools/llvm-strings/nested-archives.test

-RUN: rm -rf %t && mkdir -p %t
-RUN: llvm-ar --format=gnu crs %t/inner.a %S/Inputs/abcd
-RUN: llvm-ar --format=gnu crs %t/outer.a %t/inner.a
-RUN: llvm-strings %t/outer.a | FileCheck %s
-
-CHECK: !<arch>
-CHECK: inner.a/        0           0     0     644     72        `
-CHECK: !<arch>
-CHECK: abcd/           0           0     0     644     4         `
-CHECK: abcd
-

llvm/trunk/test/tools/llvm-strings/option-grouping.test

+## Show that llvm-strings can handle grouped short options.
+
+RUN: echo abcd > %t
+RUN: llvm-strings -af %t | FileCheck %s -DFILE=%t
+
+CHECK: [[FILE]]: abcd

llvm/trunk/test/tools/llvm-strings/radix-filename.test

-RUN: llvm-strings --print-file-name %S/Inputs/numbers \
-RUN:     | FileCheck %s --check-prefix CHECK-NONE
-RUN: llvm-strings --print-file-name -t d %S/Inputs/numbers \
-RUN:    | FileCheck %s --check-prefix CHECK-DEC --strict-whitespace
-RUN: llvm-strings --print-file-name -t o %S/Inputs/numbers \
-RUN:     | FileCheck %s --check-prefix CHECK-OCT --strict-whitespace
-RUN: llvm-strings --print-file-name -t x %S/Inputs/numbers \
-RUN:     | FileCheck %s --check-prefix CHECK-HEX --strict-whitespace
-
-CHECK-NONE: numbers: three
-CHECK-NONE: numbers: four
-CHECK-NONE: numbers: five
-CHECK-NONE: numbers: seven
-CHECK-NONE: numbers: eight
-CHECK-NONE: numbers: nine
-
-CHECK-DEC: numbers:       8 three
-CHECK-DEC: numbers:      14 four
-CHECK-DEC: numbers:      19 five
-CHECK-DEC: numbers:      28 seven
-CHECK-DEC: numbers:      34 eight
-CHECK-DEC: numbers:      40 nine
-
-CHECK-OCT: numbers:      10 three
-CHECK-OCT: numbers:      16 four
-CHECK-OCT: numbers:      23 five
-CHECK-OCT: numbers:      34 seven
-CHECK-OCT: numbers:      42 eight
-CHECK-OCT: numbers:      50 nine
-
-CHECK-HEX: numbers:       8 three
-CHECK-HEX: numbers:       e four
-CHECK-HEX: numbers:      13 five
-CHECK-HEX: numbers:      1c seven
-CHECK-HEX: numbers:      22 eight
-CHECK-HEX: numbers:      28 nine
+## Show that --radix combined with --print-file-name produces correct output.
+
+RUN: echo one > %t
+RUN: echo two >> %t
+RUN: echo three >> %t
+RUN: echo four >> %t
+RUN: echo five >> %t
+RUN: echo six >> %t
+RUN: echo seven >> %t
+RUN: echo eight >> %t
+RUN: echo nine >> %t
+RUN: echo ten >> %t
+
+RUN: llvm-strings --print-file-name %t \
+RUN:     | FileCheck %s --check-prefix CHECK-NONE -DFILE=%t --implicit-check-not={{.}}
+RUN: llvm-strings --print-file-name -t d %t \
+RUN:    | FileCheck %s --check-prefix CHECK-DEC --strict-whitespace -DFILE=%t --implicit-check-not={{.}}
+RUN: llvm-strings --print-file-name -t o %t \
+RUN:     | FileCheck %s --check-prefix CHECK-OCT --strict-whitespace -DFILE=%t --implicit-check-not={{.}}
+RUN: llvm-strings --print-file-name -t x %t \
+RUN:     | FileCheck %s --check-prefix CHECK-HEX --strict-whitespace -DFILE=%t --implicit-check-not={{.}}
+
+CHECK-NONE: [[FILE]]: three
+CHECK-NONE: [[FILE]]: four
+CHECK-NONE: [[FILE]]: five
+CHECK-NONE: [[FILE]]: seven
+CHECK-NONE: [[FILE]]: eight
+CHECK-NONE: [[FILE]]: nine
+
+CHECK-DEC: [[FILE]]:       8 three
+CHECK-DEC: [[FILE]]:      14 four
+CHECK-DEC: [[FILE]]:      19 five
+CHECK-DEC: [[FILE]]:      28 seven
+CHECK-DEC: [[FILE]]:      34 eight
+CHECK-DEC: [[FILE]]:      40 nine
+
+CHECK-OCT: [[FILE]]:      10 three
+CHECK-OCT: [[FILE]]:      16 four
+CHECK-OCT: [[FILE]]:      23 five
+CHECK-OCT: [[FILE]]:      34 seven
+CHECK-OCT: [[FILE]]:      42 eight
+CHECK-OCT: [[FILE]]:      50 nine
+
+CHECK-HEX: [[FILE]]:       8 three
+CHECK-HEX: [[FILE]]:       e four
+CHECK-HEX: [[FILE]]:      13 five
+CHECK-HEX: [[FILE]]:      1c seven
+CHECK-HEX: [[FILE]]:      22 eight
+CHECK-HEX: [[FILE]]:      28 nine

llvm/trunk/test/tools/llvm-strings/radix.test

-RUN: llvm-strings %S/Inputs/numbers | FileCheck %s -check-prefix CHECK-NONE
-RUN: llvm-strings -t d %S/Inputs/numbers | FileCheck %s -check-prefix CHECK-DEC --strict-whitespace
-RUN: llvm-strings -t o %S/Inputs/numbers | FileCheck %s -check-prefix CHECK-OCT --strict-whitespace
-RUN: llvm-strings -t x %S/Inputs/numbers | FileCheck %s -check-prefix CHECK-HEX --strict-whitespace
+## Show that llvm-strings can handle the -t/--radix switch properly.
+
+RUN: echo one > %t
+RUN: echo two >> %t
+RUN: echo three >> %t
+RUN: echo four >> %t
+RUN: echo five >> %t
+RUN: echo six >> %t
+RUN: echo seven >> %t
+RUN: echo eight >> %t
+RUN: echo nine >> %t
+RUN: echo ten >> %t
+
+RUN: llvm-strings %t | FileCheck %s -check-prefix CHECK-NONE --implicit-check-not={{.}}
+RUN: llvm-strings -t d %t | FileCheck %s -check-prefix CHECK-DEC --strict-whitespace --implicit-check-not={{.}}
+RUN: llvm-strings -t o %t | FileCheck %s -check-prefix CHECK-OCT --strict-whitespace --implicit-check-not={{.}}
+RUN: llvm-strings -t x %t | FileCheck %s -check-prefix CHECK-HEX --strict-whitespace --implicit-check-not={{.}}
+
+## Show --radix works too.
+RUN: llvm-strings --radix d %t | FileCheck %s -check-prefix CHECK-DEC --strict-whitespace
+RUN: llvm-strings --radix o %t | FileCheck %s -check-prefix CHECK-OCT --strict-whitespace
+RUN: llvm-strings --radix x %t | FileCheck %s -check-prefix CHECK-HEX --strict-whitespace
+
+## Show different syntaxes work.
+RUN: llvm-strings --radix=d %t | FileCheck %s -check-prefix CHECK-DEC --strict-whitespace
+RUN: llvm-strings -t=d %t | FileCheck %s -check-prefix CHECK-DEC --strict-whitespace
 
 CHECK-NONE: {{^}}three
 CHECK-NONE: {{^}}four
 CHECK-NONE: {{^}}five
 CHECK-NONE: {{^}}seven
 CHECK-NONE: {{^}}eight
 CHECK-NONE: {{^}}nine
 

 CHECK-OCT: {{^}}     50 nine
 
 CHECK-HEX: {{^}}      8 three
 CHECK-HEX: {{^}}      e four
 CHECK-HEX: {{^}}     13 five
 CHECK-HEX: {{^}}     1c seven
 CHECK-HEX: {{^}}     22 eight
 CHECK-HEX: {{^}}     28 nine
+
+## Show that an invalid value is rejected.
+RUN: not llvm-strings --radix z %t 2>&1 | FileCheck %s --check-prefix=INVALID
+INVALID: llvm-strings{{.*}}: for the --radix option: Cannot find option named 'z'!

llvm/trunk/test/tools/llvm-strings/response-file.test

+## Show that llvm-strings can consume a response file.
+
+RUN: echo abcd > %t
+RUN: echo --print-file-name %t > %t.rsp
+RUN: llvm-strings --radix=d @%t.rsp | FileCheck %s -DFILE=%t
+
+CHECK: [[FILE]]: 0 abcd

llvm/trunk/test/tools/llvm-strings/stdin-filename.test

+## Show that --print-file-name works when the input is standard input.
+
 RUN: echo abcd | llvm-strings -f - | FileCheck %s
+RUN: echo abcd | llvm-strings -f | FileCheck %s
 RUN: echo abcd | llvm-strings --print-file-name - | FileCheck %s
+RUN: echo abcd | llvm-strings --print-file-name | FileCheck %s
 CHECK: {standard input}: abcd

llvm/trunk/test/tools/llvm-strings/stdin.test

+## Show that llvm-strings can handle stdin input properly.
+
+## Case 1: output with single string.
+RUN: echo -n "abcdefg" | llvm-strings - | FileCheck %s --check-prefix=CASE1 --implicit-check-not={{.}}
+CASE1: abcdefg
+
+## Case 2: output too short for string.
+RUN: echo -n "abc" | llvm-strings - | FileCheck %s --implicit-check-not={{.}} --allow-empty
+
+## Case 3: output with new line.
+RUN: echo -e "abcd\nefgh" | llvm-strings - | FileCheck %s --check-prefix=CASE3 --implicit-check-not={{.}}
+CASE3:      abcd
+CASE3-NEXT: efgh
+
+## Case 4: output containing unprintable characters.
+RUN: echo -e "abcd\x00ef\x1fghij\x7fklmn" | llvm-strings - | FileCheck %s --check-prefix=CASE4 --implicit-check-not={{.}} 
+CASE4:      abcd
+CASE4-NEXT: ghij
+CASE4-NEXT: klmn
+
+## Case 5: no file name specified is equivalent to explicitly requesting stdin.
+RUN: echo -n "abcdefg" | llvm-strings | FileCheck %s --check-prefix=CASE1 --implicit-check-not={{.}}

llvm/trunk/test/tools/llvm-strings/terminator-neg.test

-RUN: echo -n abc | llvm-strings - | FileCheck -allow-empty %s
-CHECK-NOT: abc

llvm/trunk/test/tools/llvm-strings/terminator.test

-RUN: echo -n abcdefg | llvm-strings - | FileCheck %s
-CHECK: abcdefg

llvm/trunk/test/tools/llvm-strings/version.test

+## Show that --version works for llvm-strings.
+
+RUN: llvm-strings --version | FileCheck %s
+CHECK: version

llvm/trunk/test/tools/llvm-strings/whitespace.test

-RUN: echo -n abcd | llvm-strings - | FileCheck %s --strict-whitespace
+## Show that the default output format matches GNU strings.
+RUN: echo -n abcd | llvm-strings - | FileCheck %s --strict-whitespace --implicit-check-not={{.}}
 CHECK: {{^}}abcd{{$}}