tiny os.* module

Author: alicebob

cmd_scripting.go

@@ -97,6 +97,7 @@ func (m *Miniredis) runLuaScript(c *server.Peer, sha, script string, readOnly bo
 		l.Push(mod)
 		return 1
 	}))
+	l.RegisterModule("os", mkLuaOS())
 
 	_ = doScript(l, protectGlobals)
 

cmd_scripting_test.go

@@ -169,40 +169,45 @@ func TestScript(t *testing.T) {
 		"SCRIPT", "FOO",
 		proto.Error("ERR unknown subcommand 'FOO'. Try SCRIPT HELP."),
 	)
-}
 
-func TestCJSON(t *testing.T) {
-	_, c := runWithClient(t)
+	t.Run("CJSON", func(t *testing.T) {
+		mustDo(t, c,
+			"EVAL", `return cjson.decode('{"id":"foo"}')['id']`, "0",
+			proto.String("foo"),
+		)
+		mustDo(t, c,
+			"EVAL", `return cjson.encode({foo=42})`, "0",
+			proto.String(`{"foo":42}`),
+		)
 
-	mustDo(t, c,
-		"EVAL", `return cjson.decode('{"id":"foo"}')['id']`, "0",
-		proto.String("foo"),
-	)
-	mustDo(t, c,
-		"EVAL", `return cjson.encode({foo=42})`, "0",
-		proto.String(`{"foo":42}`),
-	)
+		mustContain(t, c,
+			"EVAL", `redis.encode()`, "0",
+			"Error compiling script",
+		)
+		mustContain(t, c,
+			"EVAL", `redis.encode("1", "2")`, "0",
+			"Error compiling script",
+		)
+		mustContain(t, c,
+			"EVAL", `redis.decode()`, "0",
+			"Error compiling script",
+		)
+		mustContain(t, c,
+			"EVAL", `redis.decode("{")`, "0",
+			"Error compiling script",
+		)
+		mustContain(t, c,
+			"EVAL", `redis.decode("1", "2")`, "0",
+			"Error compiling script",
+		)
+	})
 
-	mustContain(t, c,
-		"EVAL", `redis.encode()`, "0",
-		"Error compiling script",
-	)
-	mustContain(t, c,
-		"EVAL", `redis.encode("1", "2")`, "0",
-		"Error compiling script",
-	)
-	mustContain(t, c,
-		"EVAL", `redis.decode()`, "0",
-		"Error compiling script",
-	)
-	mustContain(t, c,
-		"EVAL", `redis.decode("{")`, "0",
-		"Error compiling script",
-	)
-	mustContain(t, c,
-		"EVAL", `redis.decode("1", "2")`, "0",
-		"Error compiling script",
-	)
+	t.Run("os.", func(t *testing.T) {
+		mustDo(t, c,
+			"EVAL", `return os.clock()`, "0",
+			proto.Int(42),
+		)
+	})
 }
 
 func TestLog(t *testing.T) {

integration/script_test.go

@@ -193,8 +193,9 @@ func TestLua(t *testing.T) {
 	testRaw(t, func(c *client) {
 		// c.Do("EVAL", "print(1)", "0")
 		c.Do("EVAL", `return string.format('%q', "pretty string")`, "0")
-		c.Error("Script attempted to access nonexistent global variable", "EVAL", "os.clock()", "0")
-		c.Error("Script attempted to access nonexistent global variable", "EVAL", "os.exit(42)", "0")
+		c.Error("Script attempted to access nonexistent global variable", "EVAL", "foob.clock()", "0")
+		c.DoLoosely("EVAL", "os.clock()", "0")
+		c.Error("attempt to call", "EVAL", "os.exit(42)", "0")
 		c.Do("EVAL", "return table.concat({1,2,3})", "0")
 		c.Do("EVAL", "return math.abs(-42)", "0")
 		c.Error("Script attempted to access nonexistent global variable", "EVAL", `return utf8.len("hello world")`, "0")

lua.go

@@ -299,3 +299,14 @@ func luaStatusReply(msg string) *lua.LTable {
 	tab.RawSetString("ok", lua.LString(msg))
 	return tab
 }
+
+// Our very minimal "os." lua lib.
+func mkLuaOS() map[string]lua.LGFunction {
+	return map[string]lua.LGFunction{
+		// > Returns an approximation of the amount in seconds of CPU time used by the program
+		"clock": func(l *lua.LState) int {
+			l.Push(lua.LNumber(42))
+			return 1
+		},
+	}
+}