diff mercurial/templateutil.py @ 44597:fc1fa3a07af6

templater: introduce wrapper for smartset (API)

I want to add a template function which takes a revset as an argument:

  {somefunc(..., revset(...))}
                 ^^^^^^^^^^^
                 evaluates to a revslist

This wrapper will provide a method to get an underlying smartset. It should
also be good for performance since count(revset(...)) will no longer have to
fully consume the smartset for example, but that isn't the point of this
change.

--- a/mercurial/templateutil.py	Fri Mar 20 23:30:23 2020 -0400
+++ b/mercurial/templateutil.py	Sun Mar 15 15:12:44 2020 +0900
@@ -15,6 +15,7 @@
 from . import (
     error,
     pycompat,
+    smartset,
     util,
 )
 from .utils import (
@@ -408,6 +409,74 @@
         return _unthunk(context, mapping, self._value)
 
 
+class revslist(wrapped):
+    """Wrapper for a smartset (a list/set of revision numbers)
+
+    If name specified, the revs will be rendered with the old-style list
+    template of the given name by default.
+    """
+
+    def __init__(self, repo, revs, name=None):
+        assert isinstance(revs, smartset.abstractsmartset)
+        self._repo = repo
+        self._revs = revs
+        self._name = name
+
+    def contains(self, context, mapping, item):
+        rev = unwrapinteger(context, mapping, item)
+        return rev in self._revs
+
+    def getmember(self, context, mapping, key):
+        raise error.ParseError(_(b'not a dictionary'))
+
+    def getmin(self, context, mapping):
+        makehybriditem = self._makehybriditemfunc()
+        return makehybriditem(self._revs.min())
+
+    def getmax(self, context, mapping):
+        makehybriditem = self._makehybriditemfunc()
+        return makehybriditem(self._revs.max())
+
+    def filter(self, context, mapping, select):
+        makehybriditem = self._makehybriditemfunc()
+        frevs = self._revs.filter(lambda r: select(makehybriditem(r)))
+        # once filtered, no need to support old-style list template
+        return revslist(self._repo, frevs, name=None)
+
+    def itermaps(self, context):
+        makemap = self._makemapfunc()
+        for r in self._revs:
+            yield makemap(r)
+
+    def _makehybriditemfunc(self):
+        makemap = self._makemapfunc()
+        return lambda r: hybriditem(None, r, r, makemap)
+
+    def _makemapfunc(self):
+        repo = self._repo
+        name = self._name
+        if name:
+            return lambda r: {name: r, b'ctx': repo[r]}
+        else:
+            return lambda r: {b'ctx': repo[r]}
+
+    def join(self, context, mapping, sep):
+        return joinitems(self._revs, sep)
+
+    def show(self, context, mapping):
+        if self._name:
+            srevs = [b'%d' % r for r in self._revs]
+            return _showcompatlist(context, mapping, self._name, srevs)
+        else:
+            return self.join(context, mapping, b' ')
+
+    def tobool(self, context, mapping):
+        return bool(self._revs)
+
+    def tovalue(self, context, mapping):
+        return list(self._revs)
+
+
 class _mappingsequence(wrapped):
     """Wrapper for sequence of template mappings