Merge prasoon2211/buildbot:setPropFromComm_issue2928 (PR #1590)

master/buildbot/steps/shell.py

@@ -289,19 +289,26 @@ class SetPropertyFromCommand(ShellCommand):
     name = "setproperty"
     renderables = ['property']
 
-    def __init__(self, property=None, extract_fn=None, strip=True, **kwargs):
+    def __init__(self, property=None, extract_fn=None, strip=True,
+                 includeStdout=True, includeStderr=False, **kwargs):
         self.property = property
         self.extract_fn = extract_fn
         self.strip = strip
+        self.includeStdout = includeStdout
+        self.includeStderr = includeStderr
 
         if not ((property is not None) ^ (extract_fn is not None)):
             config.error(
                 "Exactly one of property and extract_fn must be set")
 
         ShellCommand.__init__(self, **kwargs)
 
+        if self.extract_fn:
+            self.includeStderr = True
+
         self.observer = logobserver.BufferLogObserver(
-            wantStdout=True, wantStderr=self.extract_fn)
+            wantStdout=self.includeStdout,
+            wantStderr=self.includeStderr)
         self.addLogObserver('stdio', self.observer)
 
         self.property_changes = {}

master/docs/manual/cfg-buildsteps.rst

@@ -2216,12 +2216,18 @@ To avoid stripping, add ``strip=False``.
 
 The ``property`` argument can be specified as a  :ref:`Interpolate` object, allowing the property name to be built from other property values.
 
+Passing ``includeStdout=False`` (default ``True``) stops capture from stdout.
+
+Passing ``includeStderr=True`` (default ``False``) allows capture from stderr.
+
 The more advanced usage allows you to specify a function to extract properties from the command output.
 Here you can use regular expressions, string interpolation, or whatever you would like.
 In this form, :func:`extract_fn` should be passed, and not :class:`Property`.
 The :func:`extract_fn` function is called with three arguments: the exit status of the command, its standard output as a string, and its standard error as a string.
 It should return a dictionary containing all new properties.
 
+Note that passing in :func:`extract_fn` will set ``includeStderr`` to ``True``.
+
 ::
 
     def glob2list(rc, stdout, stderr):