Bug #134466 - Add a --ask-enter-invalid option. When used together with the

--ask option, interpret a single "Enter" key press as invalid input. This
helps prevent accidental acceptance of the first choice.

svn path=/main/trunk/; revision=14710

5 files changed, 48 insertions, 23 deletions

diff --git a/pym/_emerge/actions.py b/pym/_emerge/actions.py
index 916d6a8b..bd668985 100644
--- a/pym/_emerge/actions.py
+++ b/pym/_emerge/actions.py
@@ -134,6 +134,7 @@ def action_build(settings, trees, mtimedb,
 	pretend = "--pretend" in myopts
 	fetchonly = "--fetchonly" in myopts or "--fetch-all-uri" in myopts
 	ask = "--ask" in myopts
+	enter_invalid = '--ask-enter-invalid' in myopts
 	nodeps = "--nodeps" in myopts
 	oneshot = "--oneshot" in myopts or "--onlydeps" in myopts
 	tree = "--tree" in myopts
@@ -340,7 +341,7 @@ def action_build(settings, trees, mtimedb,
 			else:
 				prompt="Would you like to merge these packages?"
 		print()
-		if "--ask" in myopts and userquery(prompt) == "No":
+		if "--ask" in myopts and userquery(prompt, enter_invalid) == "No":
 			print()
 			print("Quitting.")
 			print()
@@ -441,6 +442,7 @@ def action_build(settings, trees, mtimedb,
 		return retval
 
 def action_config(settings, trees, myopts, myfiles):
+	enter_invalid = '--ask-enter-invalid' in myopts
 	if len(myfiles) != 1:
 		print(red("!!! config can only take a single package atom at this time\n"))
 		sys.exit(1)
@@ -470,7 +472,7 @@ def action_config(settings, trees, myopts, myfiles):
 				print(options[-1]+") "+pkg)
 			print("X) Cancel")
 			options.append("X")
-			idx = userquery("Selection?", options)
+			idx = userquery("Selection?", enter_invalid, responses=options)
 			if idx == "X":
 				sys.exit(0)
 			pkg = pkgs[int(idx)-1]
@@ -485,7 +487,7 @@ def action_config(settings, trees, myopts, myfiles):
 
 	print()
 	if "--ask" in myopts:
-		if userquery("Ready to configure "+pkg+"?") == "No":
+		if userquery("Ready to configure %s?" % pkg, enter_invalid) == "No":
 			sys.exit(0)
 	else:
 		print("Configuring pkg...")
@@ -1142,6 +1144,7 @@ def calc_depclean(settings, trees, ldpath_mtimes,
 	return 0, [], False, required_pkgs_total
 
 def action_deselect(settings, trees, opts, atoms):
+	enter_invalid = '--ask-enter-invalid' in opts
 	root_config = trees[settings['ROOT']]['root_config']
 	world_set = root_config.sets['selected']
 	if not hasattr(world_set, 'update'):
@@ -1184,7 +1187,7 @@ def action_deselect(settings, trees, opts, atoms):
 			if '--ask' in opts:
 				prompt = "Would you like to remove these " + \
 					"packages from your world favorites?"
-				if userquery(prompt) == 'No':
+				if userquery(prompt, enter_invalid) == 'No':
 					return os.EX_OK
 
 			remaining = set(world_set)
@@ -1679,6 +1682,7 @@ def action_search(root_config, myopts, myfiles, spinner):
 			searchinstance.output()
 
 def action_sync(settings, trees, mtimedb, myopts, myaction):
+	enter_invalid = '--ask-enter-invalid' in myopts
 	xterm_titles = "notitles" not in settings.features
 	emergelog(xterm_titles, " === sync")
 	portdb = trees[settings["ROOT"]]["porttree"].dbapi
@@ -1924,7 +1928,9 @@ def action_sync(settings, trees, mtimedb, myopts, myaction):
 
 			if (retries==0):
 				if "--ask" in myopts:
-					if userquery("Do you want to sync your Portage tree with the mirror at\n" + blue(dosyncuri) + bold("?"))=="No":
+					if userquery("Do you want to sync your Portage tree " + \
+						"with the mirror at\n" + blue(dosyncuri) + bold("?"),
+						enter_invalid) == "No":
 						print()
 						print("Quitting.")
 						print()
diff --git a/pym/_emerge/help.py b/pym/_emerge/help.py
index 0a5e9408..9d036f05 100644
--- a/pym/_emerge/help.py
+++ b/pym/_emerge/help.py
@@ -255,16 +255,29 @@ def help(myopts, havecolor=1):
 		print("              be displayed as USE=\"-bar dar -foo\"")
 		print()
 		print("       "+green("--ask")+" ("+green("-a")+" short option)")
-		print("              before performing the merge, display what ebuilds and tbz2s will")
-		print("              be installed, in the same format as when using --pretend; then")
-		print("              ask whether to continue with the merge or abort. Using --ask is")
-		print("              more efficient than using --pretend and then executing the same")
-		print("              command without --pretend, as dependencies will only need to be")
-		print("              calculated once. WARNING: If the \"Enter\" key is pressed at the")
-		print("              prompt (with no other input), it is interpreted as acceptance of")
-		print("              the first choice.  Note that the input buffer is not cleared prior")
-		print("              to the prompt, so an accidental press of the \"Enter\" key at any")
-		print("              time prior to the prompt will be interpreted as a choice!")
+		desc = "Before performing the action, display what will take place (server info for " + \
+			"--sync, --pretend output for merge, and so forth), then ask " + \
+			"whether to proceed with the action or abort.  Using --ask is more " + \
+			"efficient than using --pretend and then executing the same command " + \
+			"without --pretend, as dependencies will only need to be calculated once. " + \
+			"WARNING: If the \"Enter\" key is pressed at the prompt (with no other input), " + \
+			"it is interpreted as acceptance of the first choice.  Note that the input " + \
+			"buffer is not cleared prior to the prompt, so an accidental press of the " + \
+			"\"Enter\" key at any time prior to the prompt will be interpreted as a choice! " + \
+			"Use the --ask-enter-invalid option if you want a single \"Enter\" key " + \
+			"press to be interpreted as invalid input."
+		for line in wrap(desc, desc_width):
+			print(desc_indent + line)
+		print()
+		print("        " + green("--ask-enter-invalid"))
+		desc = "When used together with the --ask option, " + \
+			"interpret a single \"Enter\" key press as " + \
+			"invalid input. This helps prevent accidental " + \
+			"acceptance of the first choice. This option is " + \
+			"intended to be set in the make.conf(5) " + \
+			"EMERGE_DEFAULT_OPTS variable."
+		for line in wrap(desc, desc_width):
+			print(desc_indent + line)
 		print()
 		print("        " + green("--binpkg-respect-use") + \
 			" < " + turquoise("y") + " | " + turquoise("n") + " >")
diff --git a/pym/_emerge/main.py b/pym/_emerge/main.py
index b00c8fb1..a20a5e7b 100644
--- a/pym/_emerge/main.py
+++ b/pym/_emerge/main.py
@@ -49,6 +49,7 @@ if sys.hexversion >= 0x3000000:
 
 options=[
 "--ask",          "--alphabetical",
+"--ask-enter-invalid",
 "--buildpkg",     "--buildpkgonly",
 "--changed-use",
 "--changelog",    "--columns",
diff --git a/pym/_emerge/unmerge.py b/pym/_emerge/unmerge.py
index 967d7247..aefc94b3 100644
--- a/pym/_emerge/unmerge.py
+++ b/pym/_emerge/unmerge.py
@@ -27,6 +27,7 @@ def unmerge(root_config, myopts, unmerge_action,
 	if clean_world:
 		clean_world = myopts.get('--deselect') != 'n'
 	quiet = "--quiet" in myopts
+	enter_invalid = '--ask-enter-invalid' in myopts
 	settings = root_config.settings
 	sets = root_config.sets
 	vartree = root_config.trees["vartree"]
@@ -483,7 +484,8 @@ def unmerge(root_config, myopts, unmerge_action,
 		#we're done... return
 		return 0
 	if "--ask" in myopts:
-		if userquery("Would you like to unmerge these packages?")=="No":
+		if userquery("Would you like to unmerge these packages?",
+			enter_invalid) == "No":
 			# enter pretend mode for correct formatting of results
 			myopts["--pretend"] = True
 			print()
diff --git a/pym/_emerge/userquery.py b/pym/_emerge/userquery.py
index 5da23600..f177c9e8 100644
--- a/pym/_emerge/userquery.py
+++ b/pym/_emerge/userquery.py
@@ -8,11 +8,12 @@ import sys
 
 from portage.output import bold, create_color_func
 
-def userquery(prompt, responses=None, colours=None):
+def userquery(prompt, enter_invalid, responses=None, colours=None):
 	"""Displays a prompt and a set of responses, then waits for a response
 	which is checked against the responses and the first to match is
-	returned.  An empty response will match the first value in responses.  The
-	input buffer is *not* cleared prior to the prompt!
+	returned. An empty response will match the first value in responses,
+	unless enter_invalid is True. The input buffer is *not* cleared prior
+	to the prompt!
 
 	prompt: a String.
 	responses: a List of Strings.
@@ -42,10 +43,12 @@ def userquery(prompt, responses=None, colours=None):
 				response=input("["+"/".join([colours[i](responses[i]) for i in range(len(responses))])+"] ")
 			else:
 				response=raw_input("["+"/".join([colours[i](responses[i]) for i in range(len(responses))])+"] ")
-			for key in responses:
-				# An empty response will match the first value in responses.
-				if response.upper()==key[:len(response)].upper():
-					return key
+			if response or not enter_invalid:
+				for key in responses:
+					# An empty response will match the
+					# first value in responses.
+					if response.upper()==key[:len(response)].upper():
+						return key
 			print("Sorry, response '%s' not understood." % response, end=' ')
 	except (EOFError, KeyboardInterrupt):
 		print("Interrupted.")