formatter: add json formatter

mercurial/formatter.py

@@ -1,80 +1,119
 # formatter.py - generic output formatting for mercurial
 #
 # Copyright 2012 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
+from i18n import _
+import encoding, util
+
 class baseformatter(object):
     def __init__(self, ui, topic, opts):
         self._ui = ui
         self._topic = topic
         self._style = opts.get("style")
         self._template = opts.get("template")
         self._item = None
     def __bool__(self):
         '''return False if we're not doing real templating so we can
         skip extra work'''
         return True
     def _showitem(self):
         '''show a formatted item once all data is collected'''
         pass
     def startitem(self):
         '''begin an item in the format list'''
         if self._item is not None:
             self._showitem()
         self._item = {}
     def data(self, **data):
         '''insert data into item that's not shown in default output'''
         self._item.update(data)
     def write(self, fields, deftext, *fielddata, **opts):
         '''do default text output while assigning data to item'''
         for k, v in zip(fields.split(), fielddata):
             self._item[k] = v
     def condwrite(self, cond, fields, deftext, *fielddata, **opts):
         '''do conditional write (primarily for plain formatter)'''
         for k, v in zip(fields.split(), fielddata):
             self._item[k] = v
     def plain(self, text, **opts):
         '''show raw text for non-templated mode'''
         pass
     def end(self):
         '''end output for the formatter'''
         if self._item is not None:
             self._showitem()
 
 class plainformatter(baseformatter):
     '''the default text output scheme'''
     def __init__(self, ui, topic, opts):
         baseformatter.__init__(self, ui, topic, opts)
     def __bool__(self):
         return False
     def startitem(self):
         pass
     def data(self, **data):
         pass
     def write(self, fields, deftext, *fielddata, **opts):
         self._ui.write(deftext % fielddata, **opts)
     def condwrite(self, cond, fields, deftext, *fielddata, **opts):
         '''do conditional write'''
         if cond:
             self._ui.write(deftext % fielddata, **opts)
     def plain(self, text, **opts):
         self._ui.write(text, **opts)
     def end(self):
         pass
 
 class debugformatter(baseformatter):
     def __init__(self, ui, topic, opts):
         baseformatter.__init__(self, ui, topic, opts)
         self._ui.write("%s = [\n" % self._topic)
     def _showitem(self):
         self._ui.write("    " + repr(self._item) + ",\n")
     def end(self):
         baseformatter.end(self)
         self._ui.write("]\n")
 
+class jsonformatter(baseformatter):
+    def __init__(self, ui, topic, opts):
+        baseformatter.__init__(self, ui, topic, opts)
+        self._ui.write("[")
+        self._ui._first = True
+    def _showitem(self):
+        if self._ui._first:
+            self._ui._first = False
+        else:
+            self._ui.write(",")
+
+        self._ui.write("\n {\n")
+        first = True
+        for k, v in sorted(self._item.items()):
+            if first:
+                first = False
+            else:
+                self._ui.write(",\n")
+            if isinstance(v, int):
+                self._ui.write('  "%s": %d' % (k, v))
+            else:
+                self._ui.write('  "%s": "%s"' % (k, encoding.jsonescape(v)))
+        self._ui.write("\n }")
+    def end(self):
+        baseformatter.end(self)
+        self._ui.write("\n]\n")
+
 def formatter(ui, topic, opts):
-    if ui.configbool('ui', 'formatdebug'):
+    template = opts.get("template", "")
+    if template == "json":
+        return jsonformatter(ui, topic, opts)
+    elif template == "debug":
         return debugformatter(ui, topic, opts)
+    elif template != "":
+        raise util.Abort(_("custom templates not yet supported"))
+    elif ui.configbool('ui', 'formatdebug'):
+        return debugformatter(ui, topic, opts)
+    elif ui.configbool('ui', 'formatjson'):
+        return jsonformatter(ui, topic, opts)
     return plainformatter(ui, topic, opts)