cmdutil: add Rust rendering of graphs

Summary:
Allow rendering of graphs using renderdag by setting `experimental.graph.renderer` to `ascii`, `ascii-large` or `lines`.

The minimum height of each row can be set using `experimental.graph.min-row-height`.

Reviewed By: quark-zju

Differential Revision: D19272580

fbshipit-source-id: ac5eff8446bd3c09d07624a193195b4224055ffc

eden/scm/edenscm/mercurial/cmdutil.py

@@ -19,6 +19,9 @@ import re
 import stat
 import tempfile
 
+# pyre-fixme[21]: Could not find `bindings`.
+from bindings import renderdag
+
 from . import (
     bookmarks,
     changelog,
@@ -3026,6 +3029,10 @@ def _graphnodeformatter(ui, displayer):
 def displaygraph(
     ui, repo, dag, displayer, edgefn, getrenamed=None, filematcher=None, props=None
 ):
+    if ui.config("experimental", "graph.renderer") != "legacy":
+        rustdisplaygraph(ui, repo, dag, displayer, getrenamed, filematcher, props)
+        return
+
     props = props or {}
     formatnode = _graphnodeformatter(ui, displayer)
     state = graphmod.asciistate()
@@ -3082,6 +3089,62 @@ def displaygraph(
     displayer.close()
 
 
+def rustdisplaygraph(
+    ui,
+    repo,
+    dag,
+    displayer,
+    getrenamed=None,
+    filematcher=None,
+    props=None,
+    reserved=None,
+):
+    props = props or {}
+    formatnode = _graphnodeformatter(ui, displayer)
+    renderers = {
+        "ascii": (renderdag.ascii, 2),
+        "ascii-large": (renderdag.asciilarge, 2),
+        "lines": (renderdag.boxdrawing, 2),
+    }
+    renderer, minheight = renderers.get(
+        ui.config("experimental", "graph.renderer"), (renderdag.ascii, 2)
+    )
+    if ui.configbool("experimental", "graphshorten"):
+        minheight = 1
+    minheight = ui.configint("experimental", "graph.min-row-height", minheight)
+    renderer = renderer(minheight)
+
+    if reserved:
+        for rev in reserved:
+            renderer.reserve(rev)
+
+    for (rev, _type, ctx, parents) in dag:
+        char = formatnode(repo, ctx)
+        copies = None
+        if getrenamed and ctx.rev():
+            copies = []
+            for fn in ctx.files():
+                rename = getrenamed(fn, ctx.rev())
+                if rename:
+                    copies.append((fn, rename[0]))
+        revmatchfn = None
+        if filematcher is not None:
+            revmatchfn = filematcher(ctx.rev())
+        width = renderer.width(rev, parents)
+        displayer.show(
+            ctx,
+            copies=copies,
+            matchfn=revmatchfn,
+            _graphwidth=width,
+            **pycompat.strkwargs(props)
+        )
+        msg = displayer.hunk.pop(rev)
+        ui.write(renderer.nextrow(rev, parents, char, msg).encode("utf-8"))
+        displayer.flush(ctx)
+
+    displayer.close()
+
+
 def graphlog(ui, repo, pats, opts):
     # Parameters are identical to log command ones
     revs, expr, filematcher = getgraphlogrevs(repo, pats, opts)

eden/scm/edenscm/mercurial/configitems.py

@@ -273,6 +273,8 @@ coreconfigitem("experimental", "exportableenviron", default=list)
 coreconfigitem("experimental", "extendedheader.index", default=None)
 coreconfigitem("experimental", "extendedheader.similarity", default=False)
 coreconfigitem("experimental", "format.compression", default="zlib")
+coreconfigitem("experimental", "graph.renderer", default="legacy")
+coreconfigitem("experimental", "graph.min-row-height", default=dynamicdefault)
 coreconfigitem("experimental", "graphshorten", default=False)
 coreconfigitem("experimental", "graphstyle.parent", default=dynamicdefault)
 coreconfigitem("experimental", "graphstyle.missing", default=dynamicdefault)