Options

strict-whitespace

When the --strict-whitespace option is not provided, FileCheck ignores differences between spaces and tabs. Additionally multiple spaces are ignored and treated as one space.

Example

The following check file without--strict-whitespace.check:

CHECK: String1   String2           String3

will pass on any of the following inputs:

printf "String1 String2 String3" | filecheck without--strict-whitespace.check
printf "String1  String2          String3" | filecheck without--strict-whitespace.check
printf "   String1\tString2\t\t\tString3 " | filecheck without--strict-whitespace.check

Adding --strict-whitespace disables this behavior.

match-full-lines

When the --match-full-lines option is not provided, FileCheck does not match full lines.

Example

The following check file without--match-full-lines.check:

CHECK: tring1
CHECK: ring2
CHECK: String3

will pass on the following input:

printf "String1\nString2\nString3" | filecheck without--match-full-lines.check

The --match-full-lines disables this behavior.

Strict mode

Additionally, when the --strict-whitespace option is also provided, FileCheck does not allow leading and trailing whitespaces.

The following input: printf "String1\nString2\nString3" will only be matched with the following check file:

CHECK:String1
CHECK:String2
CHECK:String3

Notice absence of spaces between CHECK: and the lines.

$ printf "String1\nString2\nString3" | filecheck strict-mode.check --strict-whitespace --match-full-lines
...filecheck
$ echo $?
0

check-prefix

The --check-prefix option allows changing a default match keyword CHECK to an arbitrary keyword. This is useful when you want to test different behavior in the same file:

RUN: printf "String1" | %FILECHECK_EXEC %s --check-prefix STRING1
RUN: printf "String2" | %FILECHECK_EXEC %s --check-prefix STRING2
STRING1: String1
STRING2: String2

One usual case is testing of how a program behaves when it is run with or without a specific option.

implicit-check-not

The --implicit-check-not option adds implicit CHECK-NOT check that works on every input line.

FileCheck.py follows LLVM FileCheck in the following implementation details:

• The implicit checks are substring-matched i.e. their are in checks, not == checks.
• The implicit checks are case sensitive, so error check will not match ERROR in the input.
• The implicit check has lower priority than the positive CHECK* checks, but it has higher priority than negative CHECK-NOT checks.
• To provide multiple implicit checks, duplicate the argument --implicit-check-not <your check> multiple times.

Example

A very useful application of this option is to add implicit --implicit-check-not error --implicit-check-not warning checks to make sure that the input never has lines that contain error or warning in them.