buildman: Allow showing the list of boards with -n

As well as showing the number of boards, allow showing the actual list of
boards that would be built, if -v is provided.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/buildman/README

@@ -141,7 +141,7 @@ means to build all arm boards except nvidia, freescale and anything ending
 with 'ball'.
 
 It is convenient to use the -n option to see what will be built based on
-the subset given.
+the subset given. Use -v as well to get an actual list of boards.
 
 Buildman does not store intermediate object files. It optionally copies
 the binary output into a directory when a build is successful. Size

tools/buildman/board.py

@@ -249,15 +249,15 @@ class Boards:
             exclude: List of boards to exclude, regardless of 'args'
 
         Returns:
-            Dictionary which holds the number of boards which were selected
+            Dictionary which holds the list of boards which were selected
             due to each argument, arranged by argument.
         """
         result = {}
         terms = self._BuildTerms(args)
 
-        result['all'] = 0
+        result['all'] = []
         for term in terms:
-            result[str(term)] = 0
+            result[str(term)] = []
 
         exclude_list = []
         for expr in exclude:
@@ -285,7 +285,7 @@ class Boards:
             if build_it:
                 board.build_it = True
                 if matching_term:
-                    result[matching_term] += 1
+                    result[matching_term].append(board.target)
-                result['all'] += 1
+                result['all'].append(board.target)
 
         return result

tools/buildman/control.py

@@ -48,9 +48,9 @@ def ShowActions(series, why_selected, boards_selected, builder, options):
     Args:
         series: Series object
         why_selected: Dictionary where each key is a buildman argument
-                provided by the user, and the value is the boards brought
+                provided by the user, and the value is the list of boards
-                in by that argument. For example, 'arm' might bring in
+                brought in by that argument. For example, 'arm' might bring
-                400 boards, so in this case the key would be 'arm' and
+                in 400 boards, so in this case the key would be 'arm' and
                 the value would be a list of board names.
         boards_selected: Dict of selected boards, key is target name,
                 value is Board object
@@ -75,9 +75,11 @@ def ShowActions(series, why_selected, boards_selected, builder, options):
     print
     for arg in why_selected:
         if arg != 'all':
-            print arg, ': %d boards' % why_selected[arg]
+            print arg, ': %d boards' % len(why_selected[arg])
+            if options.verbose:
+                print '   %s' % ' '.join(why_selected[arg])
     print ('Total boards to build for each commit: %d\n' %
-            why_selected['all'])
+            len(why_selected['all']))
 
 def DoBuildman(options, args, toolchains=None, make_func=None, boards=None,
                clean_dir=False):
@@ -221,6 +223,7 @@ def DoBuildman(options, args, toolchains=None, make_func=None, boards=None,
                     options.git_dir, count, series=None, allow_overwrite=True)
     else:
         series = None
+        if not options.dry_run:
             options.verbose = True
             if not options.summary:
                 options.show_errors = True