todo trouble + add ocaml

lua/colinzhao/lazy/trouble.lua

@@ -1,3 +1,37 @@
+local tagIdx = {}
+local tags = {
+  [0] = '',
+  [1] = 'FIX',
+  [2] = 'TODO',
+  [3] = 'WARN',
+  [4] = 'NOTE',
+}
+local numTags = 0
+for key, value in pairs(tags) do
+  tagIdx[value] = key
+  numTags = numTags + 1
+end
+
+local todoFilter = function(view, inc)
+  local f = view:get_filter 'tag'
+  local tag = tags[((tagIdx[f and f.filter.tag] or 0) + inc) % numTags]
+  view:filter({ tag = tag }, {
+    id = 'tag',
+    template = '{hl:Title}Filter:{hl} {tag}',
+    del = tag == '',
+  })
+end
+
+local diagnosticsFilter = function(view, inc)
+  local f = view:get_filter 'severity'
+  local severity = ((f and f.filter.severity or 0) + inc) % 5
+  view:filter({ severity = severity }, {
+    id = 'severity',
+    template = '{hl:Title}Filter:{hl} {severity}',
+    del = severity == 0,
+  })
+end
+
 return {
   'folke/trouble.nvim',
   opts = {
@@ -5,7 +39,44 @@ return {
     win = {
       size = 0.4,
     },
-  }, -- for default options, refer to the configuration section for custom setup.
+    ---@type table<string, trouble.Mode>
+    modes = {
+      diagnostics = {
+        mode = 'diagnostics',
+        keys = {
+          s = {
+            action = function(view)
+              diagnosticsFilter(view, 1)
+            end,
+            desc = 'Cycle Severity Filter Forward',
+          },
+          S = {
+            action = function(view)
+              diagnosticsFilter(view, -1)
+            end,
+            desc = 'Cycle Severity Filter Backward',
+          },
+        },
+      },
+      todo = {
+        mode = 'todo',
+        keys = {
+          s = {
+            action = function(view)
+              todoFilter(view, 1)
+            end,
+            desc = 'Cycle Tag Filter Forward',
+          },
+          S = {
+            action = function(view)
+              todoFilter(view, -1)
+            end,
+            desc = 'Cycle Tag Filter Backward',
+          },
+        },
+      },
+    },
+  },
   cmd = 'Trouble',
   keys = {
     {
@@ -13,6 +84,11 @@ return {
       '<cmd>Trouble diagnostics toggle focus=true<cr>',
       desc = 'Diagnostics (Trouble)',
     },
+    {
+      '<leader>to',
+      '<cmd>Trouble todo toggle focus=true<cr>',
+      desc = 'Todo (Trouble)',
+    },
     {
       '<leader>ts',
       '<cmd>Trouble symbols toggle focus=true<cr>',