revset: move subscript relation functions to its own dict
authorAnton Shestakov <av6@dwimlabs.net>
Thu, 13 Dec 2018 17:18:57 +0800
changeset 40931 e54bfde922f2
parent 40930 fcdff048a8e5
child 40932 dc38d976ff4d
revset: move subscript relation functions to its own dict This will help adding more relation functions in extensions. We skip short names (that consist of one letter) while raising UnknownIdentifier because such names cannot be suggested anyway: the similarity cutoff in dispatch._getsimilar() is currently 0.6.
mercurial/revset.py
tests/test-revset.t
--- a/mercurial/revset.py	Thu Dec 13 00:18:47 2018 -0500
+++ b/mercurial/revset.py	Thu Dec 13 17:18:57 2018 +0800
@@ -218,6 +218,15 @@
 def relationset(repo, subset, x, y, order):
     raise error.ParseError(_("can't use a relation in this context"))
 
+def generationsrel(repo, subset, x, rel, n, order):
+    # TODO: support range, rewrite tests, and drop startdepth argument
+    # from ancestors() and descendants() predicates
+    if n <= 0:
+        n = -n
+        return _ancestors(repo, subset, x, startdepth=n, stopdepth=n + 1)
+    else:
+        return _descendants(repo, subset, x, startdepth=n, stopdepth=n + 1)
+
 def relsubscriptset(repo, subset, x, y, z, order):
     # this is pretty basic implementation of 'x#y[z]' operator, still
     # experimental so undocumented. see the wiki for further ideas.
@@ -225,17 +234,11 @@
     rel = getsymbol(y)
     n = getinteger(z, _("relation subscript must be an integer"))
 
-    # TODO: perhaps this should be a table of relation functions
-    if rel in ('g', 'generations'):
-        # TODO: support range, rewrite tests, and drop startdepth argument
-        # from ancestors() and descendants() predicates
-        if n <= 0:
-            n = -n
-            return _ancestors(repo, subset, x, startdepth=n, stopdepth=n + 1)
-        else:
-            return _descendants(repo, subset, x, startdepth=n, stopdepth=n + 1)
+    if rel in subscriptrelations:
+        return subscriptrelations[rel](repo, subset, x, rel, n, order)
 
-    raise error.UnknownIdentifier(rel, ['generations'])
+    relnames = [r for r in subscriptrelations.keys() if len(r) > 1]
+    raise error.UnknownIdentifier(rel, relnames)
 
 def subscriptset(repo, subset, x, y, order):
     raise error.ParseError(_("can't use a subscript in this context"))
@@ -2215,6 +2218,11 @@
     "parentpost": parentpost,
 }
 
+subscriptrelations = {
+    "g": generationsrel,
+    "generations": generationsrel,
+}
+
 def lookupfn(repo):
     return lambda symbol: scmutil.isrevsymbol(repo, symbol)
 
--- a/tests/test-revset.t	Thu Dec 13 00:18:47 2018 -0500
+++ b/tests/test-revset.t	Thu Dec 13 17:18:57 2018 +0800
@@ -649,6 +649,17 @@
   hg: parse error: relation subscript must be an integer
   [255]
 
+suggested relations
+
+  $ hg debugrevspec '.#generafions[0]'
+  hg: parse error: unknown identifier: generafions
+  (did you mean generations?)
+  [255]
+
+  $ hg debugrevspec '.#f[0]'
+  hg: parse error: unknown identifier: f
+  [255]
+
 parsed tree at stages:
 
   $ hg debugrevspec -p all '()'