Merge pull request #16328 from gpanders/diagnostic-prefix-hi

runtime/doc/diagnostic.txt

@@ -375,8 +375,11 @@ config({opts}, {namespace})                          *vim.diagnostic.config()*
 
                                  • float: Options for floating windows:
                                    • severity: See |diagnostic-severity|.
-                                   • show_header: (boolean, default true) Show
+                                   • header: (string or table) String to use
-                                     "Diagnostics:" header
+                                     as the header for the floating window. If
+                                     a table, it is interpreted as a [text,
+                                     hl_group] tuple. Defaults to
+                                     "Diagnostics:".
                                    • source: (string) Include the diagnostic
                                      source in the message. One of "always" or
                                      "if_many".
@@ -384,17 +387,24 @@ config({opts}, {namespace})                          *vim.diagnostic.config()*
                                      a diagnostic as input and returns a
                                      string. The return value is the text used
                                      to display the diagnostic.
-                                   • prefix: (function or string) Prefix each
+                                   • prefix: (function, string, or table)
-                                     diagnostic in the floating window. If a
+                                     Prefix each diagnostic in the floating
-                                     function, it must have the signature
+                                     window. If a function, it must have the
-                                     (diagnostic, i, total) -> string, where
+                                     signature (diagnostic, i, total) ->
-                                     {i} is the index of the diagnostic being
+                                     (string, string), where {i} is the index
-                                     evaluated and {total} is the total number
+                                     of the diagnostic being evaluated and
-                                     of diagnostics displayed in the window.
+                                     {total} is the total number of
-                                     The returned string is prepended to each
+                                     diagnostics displayed in the window. The
-                                     diagnostic in the window. Otherwise, if
+                                     function should return a string which is
+                                     prepended to each diagnostic in the
+                                     window as well as an (optional) highlight
+                                     group which will be used to highlight the
+                                     prefix. If {prefix} is a table, it is
+                                     interpreted as a [text, hl_group] tuple
+                                     as in |nvim_echo()|; otherwise, if
                                      {prefix} is a string, it is prepended to
-                                     each diagnostic.
+                                     each diagnostic in the window with no
+                                     highlight.
 
                                  • update_in_insert: (default false) Update
                                    diagnostics in Insert mode (if false,
@@ -616,9 +626,11 @@ open_float({bufnr}, {opts})                      *vim.diagnostic.open_float()*
                                |vim.diagnostic.config()|.
                              • severity: See |diagnostic-severity|. Overrides
                                the setting from |vim.diagnostic.config()|.
-                             • show_header: (boolean, default true) Show
+                             • header: (string or table) String to use as the
-                               "Diagnostics:" header. Overrides the setting
+                               header for the floating window. If a table, it
-                               from |vim.diagnostic.config()|.
+                               is interpreted as a [text, hl_group] tuple.
+                               Overrides the setting from
+                               |vim.diagnostic.config()|.
                              • source: (string) Include the diagnostic source
                                in the message. One of "always" or "if_many".
                                Overrides the setting from
@@ -628,9 +640,10 @@ open_float({bufnr}, {opts})                      *vim.diagnostic.open_float()*
                                return value is the text used to display the
                                diagnostic. Overrides the setting from
                                |vim.diagnostic.config()|.
-                             • prefix: (function or string) Prefix each
+                             • prefix: (function, string, or table) Prefix
-                               diagnostic in the floating window. Overrides
+                               each diagnostic in the floating window.
-                               the setting from |vim.diagnostic.config()|.
+                               Overrides the setting from
+                               |vim.diagnostic.config()|.
 
                 Return: ~
                     tuple ({float_bufnr}, {win_id})

runtime/lua/vim/diagnostic.lua

@@ -539,17 +539,24 @@ end
 ---                its severity. Otherwise, all signs use the same priority.
 ---       - float: Options for floating windows:
 ---                  * severity: See |diagnostic-severity|.
----                  * show_header: (boolean, default true) Show "Diagnostics:" header
+---                  * header: (string or table) String to use as the header for the floating
+---                            window. If a table, it is interpreted as a [text, hl_group] tuple.
+---                            Defaults to "Diagnostics:".
 ---                  * source: (string) Include the diagnostic source in
 ---                            the message. One of "always" or "if_many".
 ---                  * format: (function) A function that takes a diagnostic as input and returns a
 ---                            string. The return value is the text used to display the diagnostic.
----                  * prefix: (function or string) Prefix each diagnostic in the floating window. If
+---                  * prefix: (function, string, or table) Prefix each diagnostic in the floating
----                            a function, it must have the signature (diagnostic, i, total) -> string,
+---                            window. If a function, it must have the signature (diagnostic, i,
----                            where {i} is the index of the diagnostic being evaluated and {total} is
+---                            total) -> (string, string), where {i} is the index of the diagnostic
----                            the total number of diagnostics displayed in the window. The returned
+---                            being evaluated and {total} is the total number of diagnostics
----                            string is prepended to each diagnostic in the window. Otherwise,
+---                            displayed in the window. The function should return a string which
----                            if {prefix} is a string, it is prepended to each diagnostic.
+---                            is prepended to each diagnostic in the window as well as an
+---                            (optional) highlight group which will be used to highlight the
+---                            prefix. If {prefix} is a table, it is interpreted as a [text,
+---                            hl_group] tuple as in |nvim_echo()|; otherwise, if {prefix} is a
+---                            string, it is prepended to each diagnostic in the window with no
+---                            highlight.
 ---       - update_in_insert: (default false) Update diagnostics in Insert mode (if false,
 ---                           diagnostics are updated on InsertLeave)
 ---       - severity_sort: (default false) Sort diagnostics by severity. This affects the order in
@@ -1158,14 +1165,15 @@ end
 ---                             from |vim.diagnostic.config()|.
 ---            - severity: See |diagnostic-severity|. Overrides the setting from
 ---                        |vim.diagnostic.config()|.
----            - show_header: (boolean, default true) Show "Diagnostics:" header. Overrides the
+---            - header: (string or table) String to use as the header for the floating window. If a
----                           setting from |vim.diagnostic.config()|.
+---                      table, it is interpreted as a [text, hl_group] tuple. Overrides the setting
+---                      from |vim.diagnostic.config()|.
 ---            - source: (string) Include the diagnostic source in the message. One of "always" or
 ---                      "if_many". Overrides the setting from |vim.diagnostic.config()|.
 ---            - format: (function) A function that takes a diagnostic as input and returns a
 ---                      string. The return value is the text used to display the diagnostic.
 ---                      Overrides the setting from |vim.diagnostic.config()|.
----            - prefix: (function or string) Prefix each diagnostic in the floating window.
+---            - prefix: (function, string, or table) Prefix each diagnostic in the floating window.
 ---                      Overrides the setting from |vim.diagnostic.config()|.
 ---@return tuple ({float_bufnr}, {win_id})
 function M.open_float(bufnr, opts)
@@ -1237,11 +1245,22 @@ function M.open_float(bufnr, opts)
 
   local lines = {}
   local highlights = {}
-  local show_header = vim.F.if_nil(opts.show_header, true)
+  local header = if_nil(opts.header, "Diagnostics:")
-  if show_header then
+  if header then
-    table.insert(lines, "Diagnostics:")
+    vim.validate { header = { header, function(v)
+      return type(v) == "string" or type(v) == "table"
+    end, "'string' or 'table'" } }
+    if type(header) == "table" then
+      -- Don't insert any lines for an empty string
+      if string.len(if_nil(header[1], "")) > 0 then
+        table.insert(lines, header[1])
+        table.insert(highlights, {0, header[2] or "Bold"})
+      end
+    elseif #header > 0 then
+      table.insert(lines, header)
       table.insert(highlights, {0, "Bold"})
     end
+  end
 
   if opts.format then
     diagnostics = reformat_diagnostics(opts.format, diagnostics)
@@ -1254,18 +1273,28 @@ function M.open_float(bufnr, opts)
   local prefix_opt = if_nil(opts.prefix, (scope == "cursor" and #diagnostics <= 1) and "" or function(_, i)
       return string.format("%d. ", i)
   end)
+
+  local prefix, prefix_hl_group
   if prefix_opt then
     vim.validate { prefix = { prefix_opt, function(v)
-      return type(v) == "string" or type(v) == "function"
+      return type(v) == "string" or type(v) == "table" or type(v) == "function"
-    end, "'string' or 'function'" } }
+    end, "'string' or 'table' or 'function'" } }
+    if type(prefix_opt) == "string" then
+      prefix, prefix_hl_group = prefix_opt, "NormalFloat"
+    elseif type(prefix_opt) == "table" then
+      prefix, prefix_hl_group = prefix_opt[1] or "", prefix_opt[2] or "NormalFloat"
+    end
   end
 
   for i, diagnostic in ipairs(diagnostics) do
-    local prefix = type(prefix_opt) == "string" and prefix_opt or prefix_opt(diagnostic, i, #diagnostics)
+    if prefix_opt and type(prefix_opt) == "function" then
+      prefix, prefix_hl_group = prefix_opt(diagnostic, i, #diagnostics)
+      prefix, prefix_hl_group = prefix or "", prefix_hl_group or "NormalFloat"
+    end
     local hiname = floating_highlight_map[diagnostic.severity]
     local message_lines = vim.split(diagnostic.message, '\n')
     table.insert(lines, prefix..message_lines[1])
-    table.insert(highlights, {#prefix, hiname})
+    table.insert(highlights, {#prefix, hiname, prefix_hl_group})
     for j = 2, #message_lines do
       table.insert(lines, string.rep(' ', #prefix) .. message_lines[j])
       table.insert(highlights, {0, hiname})
@@ -1278,8 +1307,10 @@ function M.open_float(bufnr, opts)
   end
   local float_bufnr, winnr = require('vim.lsp.util').open_floating_preview(lines, 'plaintext', opts)
   for i, hi in ipairs(highlights) do
-    local prefixlen, hiname = unpack(hi)
+    local prefixlen, hiname, prefix_hiname = unpack(hi)
-    -- Start highlight after the prefix
+    if prefix_hiname then
+      vim.api.nvim_buf_add_highlight(float_bufnr, -1, prefix_hiname, i-1, 0, prefixlen)
+    end
     vim.api.nvim_buf_add_highlight(float_bufnr, -1, hiname, i-1, prefixlen, -1)
   end
 

test/functional/lua/diagnostic_spec.lua

@@ -1277,6 +1277,44 @@ describe('vim.diagnostic', function()
   end)
 
   describe('open_float()', function()
+    it('can display a header', function()
+      eq({'Diagnostics:', '1. Syntax error'}, exec_lua [[
+        local diagnostics = {
+          make_error("Syntax error", 0, 1, 0, 3),
+        }
+        vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
+        vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
+        local float_bufnr, winnr = vim.diagnostic.open_float()
+        local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
+        vim.api.nvim_win_close(winnr, true)
+        return lines
+      ]])
+
+      eq({"We're no strangers to love...", '1. Syntax error'}, exec_lua [[
+        local diagnostics = {
+          make_error("Syntax error", 0, 1, 0, 3),
+        }
+        vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
+        vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header = "We're no strangers to love..."})
+        local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
+        vim.api.nvim_win_close(winnr, true)
+        return lines
+      ]])
+
+      eq({'You know the rules', '1. Syntax error'}, exec_lua [[
+        local diagnostics = {
+          make_error("Syntax error", 0, 1, 0, 3),
+        }
+        vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
+        vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header = {'You know the rules', 'Search'}})
+        local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
+        vim.api.nvim_win_close(winnr, true)
+        return lines
+      ]])
+    end)
+
     it('can show diagnostics from the whole buffer', function()
       eq({'1. Syntax error', '2. Some warning'}, exec_lua [[
         local diagnostics = {
@@ -1285,7 +1323,7 @@ describe('vim.diagnostic', function()
         }
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header = false})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header = false})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1302,7 +1340,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         vim.api.nvim_win_set_cursor(0, {2, 1})
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header=false, scope="line"})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header=false, scope="line"})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1317,7 +1355,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         vim.api.nvim_win_set_cursor(0, {1, 1})
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header=false, scope="line", pos=1})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header=false, scope="line", pos=1})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1334,7 +1372,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         vim.api.nvim_win_set_cursor(0, {2, 2})
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header=false, scope="cursor"})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header=false, scope="cursor"})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1349,7 +1387,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         vim.api.nvim_win_set_cursor(0, {1, 1})
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header=false, scope="cursor", pos={1,3}})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header=false, scope="cursor", pos={1,3}})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1364,7 +1402,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         vim.api.nvim_win_set_cursor(0, {1, 1})
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header=false, scope="cursor", pos={0,first_line_len}})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header=false, scope="cursor", pos={0,first_line_len}})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1434,7 +1472,7 @@ describe('vim.diagnostic', function()
         }
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
-        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {show_header = false})
+        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {header = false})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return #lines
@@ -1448,7 +1486,7 @@ describe('vim.diagnostic', function()
         }
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
-        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {show_header = false, scope = "line", pos = 5})
+        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {header = false, scope = "line", pos = 5})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return #lines
@@ -1464,7 +1502,7 @@ describe('vim.diagnostic', function()
         }
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {
-          show_header = false,
+          header = false,
           source = "if_many",
         })
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
@@ -1474,7 +1512,7 @@ describe('vim.diagnostic', function()
 
       eq({"1. source x: Syntax error"}, exec_lua [[
         local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {
-          show_header = false,
+          header = false,
           source = "always",
         })
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
@@ -1489,7 +1527,7 @@ describe('vim.diagnostic', function()
         }
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, {
-          show_header = false,
+          header = false,
           source = "if_many",
         })
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
@@ -1513,7 +1551,7 @@ describe('vim.diagnostic', function()
 
         vim.diagnostic.config({severity_sort = false})
 
-        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { show_header = false })
+        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { header = false })
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1521,7 +1559,7 @@ describe('vim.diagnostic', function()
 
       eq({"1. Syntax error", "2. Error", "3. Warning", "4. Info"}, exec_lua [[
         vim.diagnostic.config({severity_sort = true})
-        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { show_header = false })
+        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { header = false })
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1529,7 +1567,7 @@ describe('vim.diagnostic', function()
 
       eq({"1. Info", "2. Warning", "3. Error", "4. Syntax error"}, exec_lua [[
         vim.diagnostic.config({severity_sort = { reverse = true } })
-        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { show_header = false })
+        local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { header = false })
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1553,7 +1591,7 @@ describe('vim.diagnostic', function()
             make_warning('Warning', 0, 0, 0, 1),
           })
 
-          local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { show_header = false })
+          local float_bufnr, winnr = vim.diagnostic.open_float(diagnostic_bufnr, { header = false })
           if not float_bufnr then
             return 0
           end
@@ -1580,7 +1618,7 @@ describe('vim.diagnostic', function()
         }
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header = false, number = "always"})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header = false})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1593,7 +1631,7 @@ describe('vim.diagnostic', function()
         }
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
-        local float_bufnr, winnr = vim.diagnostic.open_float(0, {show_header = false, prefix = ""})
+        local float_bufnr, winnr = vim.diagnostic.open_float(0, {header = false, prefix = ""})
         local lines = vim.api.nvim_buf_get_lines(float_bufnr, 0, -1, false)
         vim.api.nvim_win_close(winnr, true)
         return lines
@@ -1607,7 +1645,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         local float_bufnr, winnr = vim.diagnostic.open_float(0, {
-          show_header = false,
+          header = false,
           prefix = function(_, i, total)
             -- Only show a number if there is more than one diagnostic
             if total > 1 then
@@ -1628,7 +1666,7 @@ describe('vim.diagnostic', function()
         vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
         vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, diagnostics)
         local float_bufnr, winnr = vim.diagnostic.open_float(0, {
-          show_header = false,
+          header = false,
           prefix = function(_, i, total)
             -- Only show a number if there is more than one diagnostic
             if total > 1 then
@@ -1642,7 +1680,7 @@ describe('vim.diagnostic', function()
         return lines
       ]])
 
-      eq("Error executing lua: .../diagnostic.lua:0: prefix: expected 'string' or 'function', got 42",
+      eq("Error executing lua: .../diagnostic.lua:0: prefix: expected 'string' or 'table' or 'function', got 42",
         pcall_err(exec_lua, [[ vim.diagnostic.open_float(0, { prefix = 42 }) ]]))
     end)
   end)