tests/README: convert to markdown

Closes #6028

2 files changed, 84 insertions, 132 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 9773b86db..7424fe6bf 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -25,7 +25,7 @@ PDFPAGES = testcurl.pdf runtests.pdf
 MANDISTPAGES = runtests.1.dist testcurl.1.dist
 
 EXTRA_DIST = ftpserver.pl httpserver.pl secureserver.pl runtests.pl           \
- getpart.pm FILEFORMAT.md README stunnel.pem memanalyze.pl testcurl.pl        \
+ getpart.pm FILEFORMAT.md README.md stunnel.pem memanalyze.pl testcurl.pl     \
  valgrind.pm ftp.pm sshserver.pl sshhelp.pm pathhelp.pm testcurl.1 runtests.1 \
  serverhelp.pm tftpserver.pl rtspserver.pl directories.pm symbol-scan.pl      \
  CMakeLists.txt mem-include-scan.pl valgrind.supp extern-scan.pl              \
diff --git a/tests/README b/tests/README.md
index 209887dfc..4b524a045 100644
--- a/tests/README
+++ b/tests/README.md
@@ -1,53 +1,19 @@
-                                  _   _ ____  _
-                              ___| | | |  _ \| |
-                             / __| | | | |_) | |
-                            | (__| |_| |  _ <| |___
-                             \___|\___/|_| \_\_____|
-
-The curl Test Suite
-
- 1. Running
-  1.1 Requires to run
-  1.2 Port numbers used by test servers
-  1.3 Test servers
-  1.4 Run
-  1.5 Shell startup scripts
-  1.6 Memory test
-  1.7 Debug
-  1.8 Logs
-  1.9 Test input files
-  1.10 Code coverage
-  1.11 Remote testing
-
- 2. Numbering
-  2.1 Test case numbering
-
- 3. Write tests
-  3.1 test data
-  3.2 curl tests
-  3.3 libcurl tests
-  3.4 unit tests
-
- 4. TODO
-  4.1 More protocols
-  4.2 SOCKS auth
-
-==============================================================================
-
-1. Running
-
- 1.1 Requires to run
-
-  perl (and a unix-style shell)
-  python (and a unix-style shell, for SMB and TELNET tests)
-  python-impacket (for SMB tests)
-  diff (when a test fails, a diff is shown)
-  stunnel (for HTTPS and FTPS tests)
-  OpenSSH or SunSSH (for SCP, SFTP and SOCKS4/5 tests)
-  nghttpx (for HTTP/2 tests)
-  nroff (for --manual tests)
-
- 1.1.1 Installation of python-impacket
+# The curl Test Suite
+
+# Running
+
+## Requires to run
+
+  - perl (and a unix-style shell)
+  - python (and a unix-style shell, for SMB and TELNET tests)
+  - python-impacket (for SMB tests)
+  - diff (when a test fails, a diff is shown)
+  - stunnel (for HTTPS and FTPS tests)
+  - OpenSSH or SunSSH (for SCP, SFTP and SOCKS4/5 tests)
+  - nghttpx (for HTTP/2 tests)
+  - nroff (for --manual tests)
+
+### Installation of python-impacket
 
   The Python-based test servers support both recent Python 2 and 3.
   You can figure out your default Python interpreter with python -V
@@ -56,33 +22,33 @@ The curl Test Suite
   You can use pip or your OS' package manager to install 'impacket'.
 
   On Debian/Ubuntu the package names are:
-    Python 2: 'python-impacket'
-    Python 3: 'python3-impacket'
+
+  -  Python 2: 'python-impacket'
+  -  Python 3: 'python3-impacket'
 
   On FreeBSD the package names are:
-    Python 2: 'py27-impacket'
-    Python 3: 'py37-impacket'
+
+  -  Python 2: 'py27-impacket'
+  -  Python 3: 'py37-impacket'
 
   On any system where pip is available:
-    Python 2: 'pip2 install impacket'
-    Python 3: 'pip3 install impacket'
+
+  -  Python 2: 'pip2 install impacket'
+  -  Python 3: 'pip3 install impacket'
 
   You may also need to manually install the Python package 'six'
   as that may be a missing requirement for impacket on Python 3.
 
- 1.2 Port numbers used by test servers
-
-  Tests are written to use as few fixed fixed port numbers as possible and all
-  tests should be written to use suitable variables instead of port numbers so
-  that test cases continue to work independent on what port numbers the test
-  servers actually use.
+### Port numbers used by test servers
 
-  The remaining fixed-port test servers that are still used, use the port
-  range 8890 - 8904 by default, but can be moved with runtests' -b option.
+  All test servers run on "random" port numbers. All tests should be written
+  to use suitable variables instead of fixed port numbers so that test cases
+  continue to work independent on what port numbers the test servers actually
+  use.
 
-  See the FILEFORMAT for a listing of existing port number variables.
+  See [FILEFORMAT](FILEFORMAT.md) for the port number variables.
 
- 1.3 Test servers
+### Test servers
 
   The test suite runs simple FTP, POP3, IMAP, SMTP, HTTP and TFTP stand-alone
   servers on the ports listed above to which it makes requests. For SSL tests,
@@ -99,27 +65,28 @@ The curl Test Suite
   The HTTP server supports listening on a Unix domain socket, the default
   location is 'http.sock'.
 
- 1.4 Run
+### Run
 
-  './configure && make && make test'. This builds the test suite support code
+  `./configure && make && make test`. This builds the test suite support code
   and invokes the 'runtests.pl' perl script to run all the tests. Edit the top
   variables of that script in case you have some specific needs, or run the
   script manually (after the support code has been built).
 
-  The script breaks on the first test that doesn't do OK. Use -a to prevent
-  the script from aborting on the first error. Run the script with -v for more
-  verbose output. Use -d to run the test servers with debug output enabled as
-  well. Specifying -k keeps all the log files generated by the test intact.
-
-  Use -s for shorter output, or pass test numbers to run specific tests only
-  (like "./runtests.pl 3 4" to test 3 and 4 only). It also supports test case
-  ranges with 'to', as in "./runtests 3 to 9" which runs the seven tests from
-  3 to 9. Any test numbers starting with ! are disabled, as are any test
-  numbers found in the files data/DISABLED or data/DISABLED.local (one per
+  The script breaks on the first test that doesn't do OK. Use `-a` to prevent
+  the script from aborting on the first error. Run the script with `-v` for
+  more verbose output. Use `-d` to run the test servers with debug output
+  enabled as well. Specifying `-k` keeps all the log files generated by the
+  test intact.
+
+  Use `-s` for shorter output, or pass test numbers to run specific tests only
+  (like `./runtests.pl 3 4` to test 3 and 4 only). It also supports test case
+  ranges with 'to', as in `./runtests.pl 3 to 9` which runs the seven tests
+  from 3 to 9. Any test numbers starting with ! are disabled, as are any test
+  numbers found in the files `data/DISABLED` or `data/DISABLED.local` (one per
   line). The latter is meant for local temporary disables and will be ignored
   by git.
 
-  When -s is not present, each successful test will display on one line the
+  When `-s` is not present, each successful test will display on one line the
   test number and description and on the next line a set of flags, the test
   result, current test sequence, total number of tests to be run and an
   estimated amount of time to complete the test run. The flags consist of
@@ -134,7 +101,7 @@ The curl Test Suite
     m memory
     v valgrind
 
- 1.5 Shell startup scripts
+### Shell startup scripts
 
   Tests which use the ssh test server, SCP/SFTP/SOCKS tests, might be badly
   influenced by the output of system wide or user specific shell startup
@@ -150,51 +117,51 @@ The curl Test Suite
   output of a shell startup script.  Locate, cleanup or adjust the shell
   script.
 
- 1.6 Memory test
+### Memory test
 
   The test script will check that all allocated memory is freed properly IF
-  curl has been built with the CURLDEBUG define set. The script will
+  curl has been built with the `CURLDEBUG` define set. The script will
   automatically detect if that is the case, and it will use the
   'memanalyze.pl' script to analyze the memory debugging output.
 
   Also, if you run tests on a machine where valgrind is found, the script will
-  use valgrind to run the test with (unless you use -n) to further verify
+  use valgrind to run the test with (unless you use `-n`) to further verify
   correctness.
 
-  runtests.pl's -t option will enable torture testing mode, which runs each
+  runtests.pl's `-t` option will enable torture testing mode, which runs each
   test many times and makes each different memory allocation fail on each
   successive run.  This tests the out of memory error handling code to ensure
   that memory leaks do not occur even in those situations. It can help to
-  compile curl with CPPFLAGS=-DMEMDEBUG_LOG_SYNC when using this option, to
+  compile curl with `CPPFLAGS=-DMEMDEBUG_LOG_SYNC` when using this option, to
   ensure that the memory log file is properly written even if curl crashes.
 
- 1.7 Debug
+### Debug
 
   If a test case fails, you can conveniently get the script to invoke the
   debugger (gdb) for you with the server running and the exact same command
-  line parameters that failed. Just invoke 'runtests.pl <test number> -g' and
+  line parameters that failed. Just invoke `runtests.pl <test number> -g` and
   then just type 'run' in the debugger to perform the command through the
   debugger.
 
- 1.8 Logs
+### Logs
 
   All logs are generated in the log/ subdirectory (it is emptied first in the
-  runtests.pl script). Use runtests.pl -k to force it to keep the temporary
-  files after the test run since successful runs will clean it up otherwise.
+  runtests.pl script). They remain in there after a test run.
 
- 1.9 Test input files
+### Test input files
 
-  All test cases are put in the data/ subdirectory. Each test is stored in the
-  file named according to the test number.
+  All test cases are put in the `data/` subdirectory. Each test is stored in
+  the file named according to the test number.
 
-  See FILEFORMAT for the description of the test case files.
+  See [FILEFORMAT.md](FILEFORMAT.md) for a description of the test case file
+  format.
 
- 1.10 Code coverage
+### Code coverage
 
-  gcc provides a tool that can determine the code coverage figures for
-  the test suite.  To use it, configure curl with
-  CFLAGS='-fprofile-arcs -ftest-coverage -g -O0'.  Make sure you run the normal
-  and torture tests to get more full coverage, i.e. do:
+  gcc provides a tool that can determine the code coverage figures for the
+  test suite.  To use it, configure curl with `CFLAGS='-fprofile-arcs
+  -ftest-coverage -g -O0`.  Make sure you run the normal and torture tests to
+  get more full coverage, i.e. do:
 
     make test
     make test-torture
@@ -207,7 +174,7 @@ The curl Test Suite
   The text mode tool gcov may also be used, but it doesn't handle object files
   in more than one directory very well.
 
- 1.11 Remote testing
+### Remote testing
 
   The runtests.pl script provides some hooks to allow curl to be tested on a
   machine where perl can not be run.  The test framework in this case runs on
@@ -215,63 +182,48 @@ The curl Test Suite
   system using ssh or some other remote execution method.  See the comments at
   the beginning of runtests.pl for details.
 
-2. Numbering
-
- 2.1 Test case numbering
+## Test case numbering
 
-  Test cases used to be numbered by category, but the ranges filled
+  Test cases used to be numbered by category ranges, but the ranges filled
   up. Subsets of tests can now be selected by passing keywords to the
-  runtests.pl script via the make TFLAGS variable.
+  runtests.pl script via the make `TFLAGS` variable.
 
-  New tests should now be added by finding a free number in
-  tests/data/Makefile.inc.
+  New tests are added by finding a free number in `tests/data/Makefile.inc`.
 
-3. Write tests
+## Write tests
 
   Here's a quick description on writing test cases. We basically have three
   kinds of tests: the ones that test the curl tool, the ones that build small
   applications and test libcurl directly and the unit tests that test
   individual (possibly internal) functions.
 
- 3.1 test data
+### test data
 
   Each test has a master file that controls all the test data. What to read,
   what the protocol exchange should look like, what exit code to expect and
   what command line arguments to use etc.
 
-  These files are tests/data/test[num] where [num] is described in section 2
-  of this document, and the XML-like file format of them is described in the
-  separate tests/FILEFORMAT document.
+  These files are `tests/data/test[num]` where `[num]` is just a unique
+  identifier described above, and the XML-like file format of them is
+  described in the separate [FILEFORMAT.md](FILEFORMAT.md) document.
 
- 3.2 curl tests
+### curl tests
 
   A test case that runs the curl tool and verifies that it gets the correct
   data, it sends the correct data, it uses the correct protocol primitives
   etc.
 
- 3.3 libcurl tests
+### libcurl tests
 
   The libcurl tests are identical to the curl ones, except that they use a
   specific and dedicated custom-built program to run instead of "curl". This
-  tool is built from source code placed in tests/libtest and if you want to
+  tool is built from source code placed in `tests/libtest` and if you want to
   make a new libcurl test that is where you add your code.
 
- 3.4 unit tests
+### unit tests
 
-  Unit tests are tests in the 13xx sequence and they are placed in tests/unit.
-  There's a tests/unit/README describing the specific set of checks and macros
-  that may be used when writing tests that verify behaviors of specific
-  individual functions.
+  Unit tests are placed in `tests/unit`. There's a tests/unit/README
+  describing the specific set of checks and macros that may be used when
+  writing tests that verify behaviors of specific individual functions.
 
   The unit tests depend on curl being built with debug enabled.
-
-4. TODO
-
- 4.1 More protocols
-
-  Add tests for TELNET, LDAP, DICT...
-
- 4.2 SOCKS auth
-
-  SOCKS4/5 test deficiencies - no proxy authentication tests as SSH (the
-  test mechanism) doesn't support them