--- a/mercurial/templater.py	Thu Aug 18 16:29:22 2016 +0900
+++ b/mercurial/templater.py	Fri Apr 22 21:29:13 2016 +0900
@@ -290,8 +290,15 @@
     return thing
 
 def evalboolean(context, mapping, arg):
+    """Evaluate given argument as boolean, but also takes boolean literals"""
     func, data = arg
-    thing = func(context, mapping, data)
+    if func is runsymbol:
+        thing = func(context, mapping, data, default=None)
+        if thing is None:
+            # not a template keyword, takes as a boolean literal
+            thing = util.parsebool(data)
+    else:
+        thing = func(context, mapping, data)
     if isinstance(thing, bool):
         return thing
     # other objects are evaluated as strings, which means 0 is True, but
@@ -516,7 +523,7 @@
     if len(args) > 2:
         fillchar = evalstring(context, mapping, args[2])
     if len(args) > 3:
-        right = util.parsebool(args[3][1])
+        right = evalboolean(context, mapping, args[3])
 
     if right:
         return text.rjust(width, fillchar)

--- a/tests/test-command-template.t	Thu Aug 18 16:29:22 2016 +0900
+++ b/tests/test-command-template.t	Fri Apr 22 21:29:13 2016 +0900
@@ -3323,6 +3323,27 @@
   hg: parse error: pad() expects an integer width
   [255]
 
+Test boolean argument passed to pad function
+
+ no crash
+
+  $ hg log -r 0 -T '{pad(rev, 10, "-", "f{"oo"}")}\n'
+  ---------0
+
+ string/literal
+
+  $ hg log -r 0 -T '{pad(rev, 10, "-", "false")}\n'
+  ---------0
+  $ hg log -r 0 -T '{pad(rev, 10, "-", false)}\n'
+  0---------
+  $ hg log -r 0 -T '{pad(rev, 10, "-", "")}\n'
+  0---------
+
+ unknown keyword is evaluated to ''
+
+  $ hg log -r 0 -T '{pad(rev, 10, "-", unknownkeyword)}\n'
+  0---------
+
 Test separate function
 
   $ hg log -r 0 -T '{separate("-", "", "a", "b", "", "", "c", "")}\n'
@@ -3332,6 +3353,23 @@
   $ hg log -r 0 --color=always -T '{separate(" ", "a", label(red, "b"), "c", label(red, ""), "d")}\n'
   a \x1b[0;31mb\x1b[0m c d (esc)
 
+Test boolean expression/literal passed to if function
+
+  $ hg log -r 0 -T '{if(rev, "rev 0 is True")}\n'
+  rev 0 is True
+  $ hg log -r 0 -T '{if(0, "literal 0 is True as well")}\n'
+  literal 0 is True as well
+  $ hg log -r 0 -T '{if("", "", "empty string is False")}\n'
+  empty string is False
+  $ hg log -r 0 -T '{if(revset(r"0 - 0"), "", "empty list is False")}\n'
+  empty list is False
+  $ hg log -r 0 -T '{if(true, "true is True")}\n'
+  true is True
+  $ hg log -r 0 -T '{if(false, "", "false is False")}\n'
+  false is False
+  $ hg log -r 0 -T '{if("false", "non-empty string is True")}\n'
+  non-empty string is True
+
 Test ifcontains function
 
   $ hg log --template '{rev} {ifcontains(rev, "2 two 0", "is in the string", "is not")}\n'