feat(health): summary in section heading #33388

Problem:
As checkhealth grows, it is increasingly hard to quickly glance through
the information.

Solution:
Show a summary of ok, warn, and error outputs per section.

3 files changed, 44 insertions, 22 deletions

diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index 5b614c1b47..d67c78adb5 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -165,7 +165,7 @@ TUI
 
 UI
 
-• todo
+• |:checkhealth| shows a summary in the header for every healthcheck.
 
 VIMSCRIPT
 
diff --git a/runtime/lua/vim/health.lua b/runtime/lua/vim/health.lua
index 294f2a357a..302cc6bc99 100644
--- a/runtime/lua/vim/health.lua
+++ b/runtime/lua/vim/health.lua
@@ -106,6 +106,7 @@
 local M = {}
 
 local s_output = {} ---@type string[]
+local check_summary = { warn = 0, error = 0 }
 
 -- From a path return a list [{name}, {func}, {type}] representing a healthcheck
 local function filepath_to_healthcheck(path)
@@ -286,6 +287,7 @@ end
 function M.warn(msg, ...)
   local input = format_report_message('⚠️ WARNING', msg, ...)
   collect_output(input)
+  check_summary['warn'] = check_summary['warn'] + 1
 end
 
 --- Reports an error.
@@ -295,6 +297,7 @@ end
 function M.error(msg, ...)
   local input = format_report_message('❌ ERROR', msg, ...)
   collect_output(input)
+  check_summary['error'] = check_summary['error'] + 1
 end
 
 local path2name = function(path)
@@ -341,6 +344,23 @@ M._complete = function()
   return rv
 end
 
+--- Gets the results heading for the current report section.
+---
+---@return string
+local function get_summary()
+  local s = ''
+  local errors = check_summary['error']
+  local warns = check_summary['warn']
+
+  s = s .. (warns > 0 and (' %2d ⚠️'):format(warns) or '')
+  s = s .. (errors > 0 and (' %2d ❌'):format(errors) or '')
+  if errors == 0 and warns == 0 then
+    s = s .. '✅'
+  end
+
+  return s
+end
+
 --- Runs the specified healthchecks.
 --- Runs all discovered healthchecks if plugin_names is empty.
 ---
@@ -397,9 +417,9 @@ function M._check(mods, plugin_names)
     local func = value[1]
     local type = value[2]
     s_output = {}
+    check_summary = { warn = 0, error = 0 }
 
     if func == '' then
-      s_output = {}
       M.error('No healthcheck found for "' .. name .. '" plugin.')
     end
     if type == 'v' then
@@ -420,10 +440,12 @@ function M._check(mods, plugin_names)
       M.error('The healthcheck report for "' .. name .. '" plugin is empty.')
     end
 
+    local report = get_summary()
+    local replen = vim.fn.strwidth(report)
     local header = {
       string.rep('=', 78),
-      -- Example: `foo.health: [ …] require("foo.health").check()`
-      ('%s: %s%s'):format(name, (' '):rep(76 - name:len() - func:len()), func),
+      -- Example: `foo.health: [ …] 1 ⚠️  5 ❌`
+      ('%s: %s%s'):format(name, (' '):rep(76 - name:len() - replen), report),
       '',
     }
 
diff --git a/test/functional/plugin/health_spec.lua b/test/functional/plugin/health_spec.lua
index 58634460c8..1b14edce1e 100644
--- a/test/functional/plugin/health_spec.lua
+++ b/test/functional/plugin/health_spec.lua
@@ -91,7 +91,7 @@ describe('vim.health', function()
       n.expect([[
 
       ==============================================================================
-      test_plug.full_render:         require("test_plug.full_render.health").check()
+      test_plug.full_render:                                              1 ⚠️  1 ❌
 
       report 1 ~
       - ✅ OK life is fine
@@ -114,7 +114,7 @@ describe('vim.health', function()
       n.expect([[
 
         ==============================================================================
-        test_plug:                                 require("test_plug.health").check()
+        test_plug:                                                                  ✅
 
         report 1 ~
         - ✅ OK everything is fine
@@ -123,7 +123,7 @@ describe('vim.health', function()
         - ✅ OK nothing to see here
 
         ==============================================================================
-        test_plug.success1:               require("test_plug.success1.health").check()
+        test_plug.success1:                                                         ✅
 
         report 1 ~
         - ✅ OK everything is fine
@@ -132,7 +132,7 @@ describe('vim.health', function()
         - ✅ OK nothing to see here
 
         ==============================================================================
-        test_plug.success2:               require("test_plug.success2.health").check()
+        test_plug.success2:                                                         ✅
 
         another 1 ~
         - ✅ OK ok
@@ -144,7 +144,7 @@ describe('vim.health', function()
       n.expect([[
 
         ==============================================================================
-        test_plug.submodule:             require("test_plug.submodule.health").check()
+        test_plug.submodule:                                                        ✅
 
         report 1 ~
         - ✅ OK everything is fine
@@ -159,7 +159,7 @@ describe('vim.health', function()
       n.expect([[
 
       ==============================================================================
-      test_plug.submodule_empty: require("test_plug.submodule_empty.health").check()
+      test_plug.submodule_empty:                                                1 ❌
 
       - ❌ ERROR The healthcheck report for "test_plug.submodule_empty" plugin is empty.
       ]])
@@ -185,7 +185,7 @@ describe('vim.health', function()
         - ❌ {Error:ERROR} No healthcheck found for "foo" plugin. |
                                                           |
         {Bar:                                                  }|
-        {h1:test_plug.success1:               require("test_pl}|
+        {h1:test_plug.success1:                               }|
                                                           |
         {h2:report 1}                                          |
         - ✅ {Ok:OK} everything is fine                        |
@@ -200,7 +200,7 @@ describe('vim.health', function()
       n.expect([[
 
         ==============================================================================
-        non_existent_healthcheck:                                                     
+        non_existent_healthcheck:                                                 1 ❌
 
         - ❌ ERROR No healthcheck found for "non_existent_healthcheck" plugin.
         ]])
@@ -218,7 +218,7 @@ describe('vim.health', function()
       n.expect([[
 
       ==============================================================================
-      test_plug.lua:                         require("test_plug.lua.health").check()
+      test_plug.lua:                                                              ✅
 
       nested lua/ directory ~
       - ✅ OK everything is ok
@@ -236,7 +236,7 @@ describe('vim.health', function()
       n.expect([[
 
       ==============================================================================
-      nest:                                           require("nest.health").check()
+      nest:                                                                       ✅
 
       healthy pack ~
       - ✅ OK healthy ok
@@ -281,14 +281,14 @@ describe(':checkhealth window', function()
       ^                                                  |
       {14:                                                  }|
       {14:                            }                      |
-      {h1:test_plug.success1:                               }|
-      {h1:require("test_plug.success1.health").check()}      |
+      {h1:test_plug.                                        }|
+      {h1:success1:                                         }|
+      {h1:                ✅}                                |
                                                         |
       {h2:report 1}                                          |
       - ✅ {32:OK} everything is fine                        |
                                                         |
       {h2:report 2}                                          |
-      - ✅ {32:OK} nothing to see here                       |
     ## grid 3
                                                         |
     ]],
@@ -324,8 +324,8 @@ describe(':checkhealth window', function()
       {14:   }                      |
       {h1:test_plug.               }|
       {h1:success1:                }|
-      {h1:require("test_plug.      }|
-      {h1:success1.health").check()}|
+      {h1:                         }|
+      {h1:                ✅}       |
                                |
       {h2:report 1}                 |
       - ✅ {32:OK} everything is    |
@@ -383,15 +383,15 @@ describe(':checkhealth window', function()
       ^                                                  |
                                                         |
                                                         |
-      test_plug.success1:                               |
-      require("test_plug.success1.health").check()      |
+      test_plug.                                        |
+      success1:                                         |
+                      ✅                                |
                                                         |
       report 1                                          |
       - ✅ OK everything is fine                        |
                                                         |
       report 2                                          |
       - ✅ OK nothing to see here                       |
-                                                        |
     ]]):format(
         top
             and [[