From 0f99f66b42158f3ecf528e16bc3a8692b6e38e22 Mon Sep 17 00:00:00 2001
From: Bob Hood <Bob.Hood.2@gmail.com>
Date: Fri, 6 Jul 2018 14:34:48 -0600
Subject: [PATCH] Refactored the Mercurial prompt code to be more efficient.

---
 vendor/clink.lua | 51 ++++++++++++++++++++++++++++--------------------
 1 file changed, 30 insertions(+), 21 deletions(-)

diff --git a/vendor/clink.lua b/vendor/clink.lua
index 5c64c03e7..153aa8f37 100644
--- a/vendor/clink.lua
+++ b/vendor/clink.lua
@@ -285,31 +285,40 @@ end
 
 local function hg_prompt_filter()
 
-    -- Colors for mercurial status
-    local colors = {
-        clean = "\x1b[1;37;40m",
-        dirty = "\x1b[31;1m",
-    }
-
-    if get_hg_dir() then
-        -- if we're inside of mercurial repo then try to detect current branch
-        local branch = get_hg_branch()
-        local color
-        if branch then
-            -- Has branch => therefore it is a mercurial folder, now figure out status
-            if get_hg_status() then
-                color = colors.clean
-            else
-                color = colors.dirty
+    local result = ""
+
+    local hg_dir = get_hg_dir()
+    if hg_dir then
+        -- Colors for mercurial status
+        local colors = {
+            clean = "\x1b[1;37;40m",
+            dirty = "\x1b[31;1m",
+        }
+
+        -- 'hg id' gives us BOTH the branch name AND an indicator that there
+        -- are uncommitted changes, in one fast(er) call
+        local pipe = io.popen("hg id 2>&1")
+        local output = pipe:read('*all')
+        local rc = { pipe:close() }
+
+        if output ~= nil and
+           string.sub(output,1,7) ~= "abort: " and             -- not an HG working copy
+           string.sub(output,1,12) ~= "000000000000" and       -- empty wc (needs update)
+           (not string.find(output, "is not recognized")) then -- 'hg' not in path
+            local color = colors.clean
+            -- split elements on space delimiter
+            local items = {}
+            for i in string.gmatch(output, "%S+") do
+                table.insert(items, i)
             end
-
-            clink.prompt.value = string.gsub(clink.prompt.value, "{hg}", color.."("..branch..")")
-            return false
+            -- if the repo hash ends with '+', the wc has uncommitted changes
+            if string.sub(items[1], -1, -1) == "+" then color = colors.dirty end
+            -- substitute the branch in directly -- already WITH parentheses.  :)
+            result = color .. items[2] -- string.sub(items[2], 1, string.len(items[2]) - 1)
         end
     end
 
-    -- No mercurial present or not in mercurial file
-    clink.prompt.value = string.gsub(clink.prompt.value, "{hg}", "")
+    clink.prompt.value = string.gsub(clink.prompt.value, "{hg}", result)
     return false
 end