add spec.list

Author: atomicptr

spec.lua

@@ -121,6 +121,12 @@ end
 ---@param spec fun(value: any): boolean
 ---@return fun(value: any): boolean
 function M.optional(spec)
+    if type(spec) ~= "function" then
+        M.fn.error(
+            string.format("spec.lua: Spec '%s' must be a function (e.g. spec.keys for tables)", M.fn.pretty_print(spec))
+        )
+    end
+
     return function(value)
         -- if no value is specified return true!
         if value == nil then
@@ -130,6 +136,31 @@ function M.optional(spec)
     end
 end
 
+---Tests if the value is a list of `spec`
+---@param spec fun(value: any): boolean
+---@return fun(value: any): boolean
+function M.list(spec)
+    if type(spec) ~= "function" then
+        M.fn.error(
+            string.format("spec.lua: Spec '%s' must be a function (e.g. spec.keys for tables)", M.fn.pretty_print(spec))
+        )
+    end
+
+    return function(value)
+        if type(value) ~= "table" then
+            return false
+        end
+
+        for _, item in ipairs(value) do
+            if not spec(item) then
+                return false
+            end
+        end
+
+        return true
+    end
+end
+
 ---Tests if all of predicates are valid
 ---@param ... fun(value: any): boolean
 ---@return fun(value: any): boolean

spec_test.lua

@@ -50,6 +50,13 @@ describe("spec.lua", function()
         assert.False(spec.optional(spec.string)(false))
     end)
 
+    it("spec.list", function()
+        assert.True(spec.list(spec.number) { 1, 2, 3, 4, 5, 6 })
+        assert.False(spec.list(spec.number) { 1, 2, 3, 4, "Test", 6 })
+        assert.False(spec.list(spec.number)(nil))
+        assert.False(spec.list(spec.number) "Test")
+    end)
+
     it("spec.all_of", function()
         assert.False(spec.valid(spec.all_of(spec.string, spec.number), nil))
         assert.True(spec.valid(spec.all_of(spec.table, spec.some), { 1, 2 }))