This folder contains mostly tests related to the semgrep-core program. For the (py)semgrep tests see the cli/tests/ folder instead.
All the semgrep-core tests can be run from the project's root
with make core-test. This will recompile the test programs if necessary.
Only running the main test program can be done with ./test. Try
./test --help for options. In particular, running just the tests
that contain the string php is done with
$ ./test -s 'php'
./test won't try to rebuild the test program to make things
faster. It is recommended to run ./test when editing language files
(.sgrep files and targets) because they will be picked up
automatically without having to rebuild the test program.
The patterns/ folder contains pairs (pattern, target). A pattern must be a
file with the .sgrep extension and a target must be a file in the target
language with the language's usual extension, known to semgrep-core.
For example, the folder for the Go language looks like this:
go
├── ...
...
├── shortassign.go
└── shortassign.sgrep
Some simple patterns are identical from one language to
another. As a convenience, if the .sgrep file exists in the
POLYGLOT folder, there's no need to have it in the language's
folder. For instance, we have:
go
├── ...
└── regexp_string.go
POLYGLOT
├── ...
└── regexp_string.sgrep
These test cases are picked up by the test program. If a match is
expected, the line just before the match must contain the string ERROR: or
the string MATCH:. As an example, the following target file expects
exactly two matches eval(s) and eval(read_line()):
# Don't match if the argument is a literal string.
eval("echo hello")
# MATCH:
eval(s)
# MATCH: on external input
eval(read_line())
Tests for just parsing are specified by placing source files into the
language's parsing/ as follows:
parsing
├── ...
├── go
│ ├── if_header_type.go
│ ├── string.go
│ └── unicode_rune.go
...
└── ...
The expectation is that each file will be parsed without an error.
The semgrep.dev live editor displays a cheatsheet for the selected language. This cheatsheet reuses some of the examples found in the language's folder. For details on what goes into the cheatsheet and how to generate it, look into the scripts:
/scripts/generate-cheatsheet/scripts/generate_cheatsheet.py