tests: Add ability to test uPy cmdline executable.

This allows to test options passed to cmdline executable, as well as the
behaviour of the REPL.

tests/cmdline/cmd_verbose.py

+# cmdline: -v -v
+# test verbose output
+print(1)

tests/cmdline/cmd_verbose.py.exp

+1
+File cmdline/cmd_verbose.py, code block '<module>' (descriptor: ######
+Raw bytecode (code_info_size=8, bytecode_size=13):
+ 08 82 23 83 45 43 00 00 02 00 00 1c 81 13 00 81
+ 64 01 32 11 5b
+arg names:
+(N_STATE 2)
+(N_EXC_STACK 0)
+(NUM_LOCAL 0)
+  bc=-3 line=1
+  bc=0 line=3
+00 LOAD_NAME print (cache=0)
+04 LOAD_CONST_SMALL_INT 1
+05 CALL_FUNCTION n=1 nkw=0
+07 POP_TOP
+08 LOAD_CONST_NONE
+09 RETURN_VALUE
+mem: total=######
+stack: ######
+GC: total: ######
+ No. of 1-blocks: ######

tests/cmdline/repl_basic.py

+# basic REPL tests
+print(1)
+OA

tests/cmdline/repl_basic.py.exp

+Micro Python ######
+>>> # basic REPL tests
+>>> print(1)
+1
+>>> print(1)
+1
+>>> 

tests/run-tests

@@ -28,6 +28,42 @@ def rm_f(fname):
 def run_micropython(pyb, args, test_file):
     if pyb is None:
         # run on PC
+        if test_file.startswith('cmdline/'):
+            # special handling for tests of the unix cmdline program
+
+            # check for any cmdline options needed for this test
+            args = [MICROPYTHON]
+            with open(test_file, 'rb') as f:
+                line = f.readline()
+                if line.startswith(b'# cmdline:'):
+                    args += line[10:].strip().split()
+
+            # run the test, possibly with redirected input
+            try:
+                if test_file.startswith('cmdline/repl_'):
+                    f = open(test_file, 'rb')
+                    output_mupy = subprocess.check_output(args, stdin=f)
+                    f.close()
+                else:
+                    output_mupy = subprocess.check_output(args + [test_file])
+            except subprocess.CalledProcessError:
+                output_mupy = b'CRASH'
+
+            # erase parts of the output that are not stable across runs
+            with open(test_file + '.exp', 'rb') as f:
+                lines_exp = f.readlines()
+            lines_mupy = [line + b'\n' for line in output_mupy.split(b'\n')]
+            if output_mupy.endswith(b'\n'):
+                lines_mupy = lines_mupy[:-1] # remove erroneous last empty line
+            if len(lines_mupy) == len(lines_exp):
+                for i in range(len(lines_mupy)):
+                    pos = lines_exp[i].find(b'######')
+                    if pos != -1 and len(lines_mupy[i]) >= pos:
+                        lines_mupy[i] = lines_mupy[i][:pos] + b'######\n'
+                output_mupy = b''.join(lines_mupy)
+
+        else:
+            # a standard test
             try:
                 output_mupy = subprocess.check_output([MICROPYTHON, '-X', 'emit=' + args.emit, test_file])
             except subprocess.CalledProcessError:
@@ -186,7 +222,7 @@ def main():
         if args.test_dirs is None:
             if pyb is None:
                 # run PC tests
-                test_dirs = ('basics', 'micropython', 'float', 'import', 'io', 'misc', 'unicode', 'extmod', 'unix')
+                test_dirs = ('basics', 'micropython', 'float', 'import', 'io', 'misc', 'unicode', 'extmod', 'unix', 'cmdline')
             else:
                 # run pyboard tests
                 test_dirs = ('basics', 'micropython', 'float', 'misc', 'extmod', 'pyb', 'pybnative', 'inlineasm')