feat(snip): trigger blacklist option

lua/typstar/autosnippets.lua

@@ -73,6 +73,7 @@ function M.snip(trigger, expand, insert, condition, priority, trigOptions)
     trigOptions = vim.tbl_deep_extend('force', {
         maxTrigLength = nil,
         wordTrig = true,
+        blacklist = {},
     }, trigOptions or {})
     return luasnip.snippet(
         {
@@ -151,10 +152,11 @@ function M.engine(trigger, opts)
     end
 
     -- matching
-    return function(line, trig)
+    return function(line_full, trig)
         if not M.snippets_toggle or not condition() then return nil end
+        local first_idx = 1
         if max_length ~= nil then
-            local first_idx = #line - max_length -- include additional char for wordtrig
+            first_idx = #line_full - max_length -- include additional char for wordtrig
             if first_idx < 0 then
                 if is_fixed_length then
                     return nil
@@ -163,10 +165,10 @@ function M.engine(trigger, opts)
                 end
             end
             if first_idx > 0 then
-                if string.byte(line, first_idx) > 127 then return nil end
+                if string.byte(line_full, first_idx) > 127 then return nil end
             end
-            line = line:sub(first_idx)
         end
+        local line = line_full:sub(first_idx)
         local whole, captures = base_engine(line, trig)
         if whole == nil then return nil end
 
@@ -175,6 +177,11 @@ function M.engine(trigger, opts)
         if opts.wordTrig and from ~= 1 and string.match(string.sub(line, from - 1, from - 1), '[%w.]') ~= nil then
             return nil
         end
+
+        -- blacklist
+        for _, w in ipairs(opts.blacklist) do
+            if line_full:sub(-#w) == w then return nil end
+        end
         return whole, captures
     end
 end

lua/typstar/snippets/math.lua

@@ -45,7 +45,7 @@ return {
     snip('ff', '(<>) / (<>) <>', { i(1, 'a'), i(2, 'b'), i(3) }, math),
 
     -- exponents
-    snip('iv', '^(-1) ', {}, math, 500, { wordTrig = false }),
+    snip('iv', '^(-1) ', {}, math, 500, { wordTrig = false, blacklist = { 'equiv' } }),
     snip('sr', '^2 ', {}, math, 500, { wordTrig = false }),
     snip('cb', '^3 ', {}, math, 500, { wordTrig = false }),
     snip('jj', '_(<>) ', { i(1, 'n') }, math, 500, { wordTrig = false }),