runtime(syntax-tests): Introduce self tests for screen dumping
Write a batch of test files with made-up syntax to serve for
additional linewise checks to be manually performed whenever
the algorithm for screen dump file generation is modified.
Define a shell variable VIM_SYNTAX_SELF_TESTING to run these
tests:
cd runtime/syntax/
VIM_SYNTAX_SELF_TESTING=1 make clean test
related: #15150
Signed-off-by: Aliaksei Budavei <0x000c70@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/syntax/testdir/input/selftestdir/README.txt b/runtime/syntax/testdir/input/selftestdir/README.txt
new file mode 100644
index 0000000..035701d
--- /dev/null
+++ b/runtime/syntax/testdir/input/selftestdir/README.txt
@@ -0,0 +1,10 @@
+The test files with made-up syntax in this directory serve for additional
+linewise checks to be manually performed whenever the algorithm managing
+screen dump file generation is modified (../../runtest.vim#RunTest()).
+
+This is mainly used for debugging and testing the syntax test suite.
+
+Please test any changes as follows:
+ cd runtime/syntax/
+ VIM_SYNTAX_SELF_TESTING=1 make clean test
+