Merge pull request #31 from TLINDEN/internal/fuzzytesting

* reorganized Eval() to return errors and call EvalItem() on each item
* fix negative shift amount error, found with fuzzy testing :)
* added fuzzy testing

Makefile

@@ -51,10 +51,13 @@ install: buildlocal
 	install -o $(UID) -g $(GID) -m 444 $(tool).1 $(PREFIX)/man/man1/
 
 clean:
-	rm -rf $(tool) coverage.out
+	rm -rf $(tool) coverage.out testdata
 
-test:
-	go test -v ./...
+test: clean
+	go test ./... $(ARGS)
+
+testfuzzy: clean
+	go test -fuzz ./... $(ARGS)
 
 singletest:
 	@echo "Call like this: make singletest TEST=TestPrepareColumns ARGS=-v"

calc.go

@@ -222,12 +222,12 @@ func (c *Calc) Prompt() string {
 }
 
 // the actual work horse, evaluate a line of calc command[s]
-func (c *Calc) Eval(line string) {
+func (c *Calc) Eval(line string) error {
 	// remove surrounding whitespace and comments, if any
 	line = strings.TrimSpace(c.Comment.ReplaceAllString(line, ""))
 
 	if line == "" {
-		return
+		return nil
 	}
 
 	items := c.Space.Split(line, -1)
@@ -239,110 +239,120 @@ func (c *Calc) Eval(line string) {
 			c.notdone = false
 		}
 
-		num, err := strconv.ParseFloat(item, 64)
+		if err := c.EvalItem(item); err != nil {
+			return err
+		}
+	}
+
+	if c.showstack && !c.stdin {
+		dots := ""
+
+		if c.stack.Len() > 5 {
+			dots = "... "
+		}
+		last := c.stack.Last(5)
+		fmt.Printf("stack: %s%s\n", dots, list2str(last))
+	}
+
+	return nil
+}
+
+func (c *Calc) EvalItem(item string) error {
+	num, err := strconv.ParseFloat(item, 64)
 
+	if err == nil {
+		c.stack.Backup()
+		c.stack.Push(num)
+	} else {
+		// try hex
+		var i int
+		_, err := fmt.Sscanf(item, "0x%x", &i)
 		if err == nil {
 			c.stack.Backup()
-			c.stack.Push(num)
-		} else {
-			// try hex
-			var i int
-			_, err := fmt.Sscanf(item, "0x%x", &i)
-			if err == nil {
-				c.stack.Backup()
-				c.stack.Push(float64(i))
-				continue
-			}
-
-			if contains(c.Constants, item) {
-				// put the constant onto the stack
-				c.stack.Backup()
-				c.stack.Push(const2num(item))
-				continue
-			}
+			c.stack.Push(float64(i))
+			return nil
+		}
 
-			if exists(c.Funcalls, item) {
-				if err := c.DoFuncall(item); err != nil {
-					fmt.Println(err)
-				} else {
-					c.Result()
-				}
-				continue
-			}
+		if contains(c.Constants, item) {
+			// put the constant onto the stack
+			c.stack.Backup()
+			c.stack.Push(const2num(item))
+			return nil
+		}
 
-			if exists(c.BatchFuncalls, item) {
-				if !c.batch {
-					fmt.Println("only supported in batch mode")
-					continue
-				}
-
-				if err := c.DoFuncall(item); err != nil {
-					fmt.Println(err)
-				} else {
-					c.Result()
-				}
-				continue
+		if exists(c.Funcalls, item) {
+			if err := c.DoFuncall(item); err != nil {
+				return Error(err.Error())
+			} else {
+				c.Result()
 			}
+			return nil
+		}
 
-			if contains(c.LuaFunctions, item) {
-				// user provided custom lua functions
-				c.EvalLuaFunction(item)
-				continue
+		if exists(c.BatchFuncalls, item) {
+			if !c.batch {
+				return Error("only supported in batch mode")
 			}
 
-			regmatches := c.Register.FindStringSubmatch(item)
-			if len(regmatches) == 3 {
-				switch regmatches[1] {
-				case ">":
-					c.PutVar(regmatches[2])
-				case "<":
-					c.GetVar(regmatches[2])
-				}
-				continue
+			if err := c.DoFuncall(item); err != nil {
+				return Error(err.Error())
+			} else {
+				c.Result()
 			}
+			return nil
+		}
 
-			// internal commands
-			if exists(c.Commands, item) {
-				c.Commands[item].Func(c)
-				continue
-			}
+		if contains(c.LuaFunctions, item) {
+			// user provided custom lua functions
+			c.EvalLuaFunction(item)
+			return nil
+		}
 
-			if exists(c.ShowCommands, item) {
-				c.ShowCommands[item].Func(c)
-				continue
+		regmatches := c.Register.FindStringSubmatch(item)
+		if len(regmatches) == 3 {
+			switch regmatches[1] {
+			case ">":
+				c.PutVar(regmatches[2])
+			case "<":
+				c.GetVar(regmatches[2])
 			}
+			return nil
+		}
 
-			if exists(c.StackCommands, item) {
-				c.StackCommands[item].Func(c)
-				continue
-			}
+		// internal commands
+		// FIXME: propagate errors
+		if exists(c.Commands, item) {
+			c.Commands[item].Func(c)
+			return nil
+		}
 
-			if exists(c.SettingsCommands, item) {
-				c.SettingsCommands[item].Func(c)
-				continue
-			}
+		if exists(c.ShowCommands, item) {
+			c.ShowCommands[item].Func(c)
+			return nil
+		}
 
-			switch item {
-			case "?":
-				fallthrough
-			case "help":
-				c.PrintHelp()
+		if exists(c.StackCommands, item) {
+			c.StackCommands[item].Func(c)
+			return nil
+		}
 
-			default:
-				fmt.Println("unknown command or operator!")
-			}
+		if exists(c.SettingsCommands, item) {
+			c.SettingsCommands[item].Func(c)
+			return nil
 		}
-	}
 
-	if c.showstack && !c.stdin {
-		dots := ""
+		switch item {
+		case "?":
+			fallthrough
+		case "help":
+			c.PrintHelp()
 
-		if c.stack.Len() > 5 {
-			dots = "... "
+		default:
+			return Error("unknown command or operator")
 		}
-		last := c.stack.Last(5)
-		fmt.Printf("stack: %s%s\n", dots, list2str(last))
 	}
+
+	return nil
 }
 
 // Execute a math function, check if it is defined just in case
@@ -355,7 +365,7 @@ func (c *Calc) DoFuncall(funcname string) error {
 	}
 
 	if function == nil {
-		panic("function not defined but in completion list")
+		return Error("function not defined but in completion list")
 	}
 
 	var args Numbers

calc_test.go

@@ -19,6 +19,8 @@ package main
 
 import (
 	"fmt"
+	"strconv"
+	"strings"
 	"testing"
 
 	lua "github.com/yuin/gopher-lua"
@@ -75,7 +77,9 @@ func TestCommentsAndWhitespace(t *testing.T) {
 
 		t.Run(testname, func(t *testing.T) {
 			for _, line := range tt.cmd {
-				calc.Eval(line)
+				if err := calc.Eval(line); err != nil {
+					t.Errorf(err.Error())
+				}
 			}
 			got := calc.stack.Last()
 
@@ -288,7 +292,9 @@ func TestCalc(t *testing.T) {
 
 		t.Run(testname, func(t *testing.T) {
 			calc.batch = tt.batch
-			calc.Eval(tt.cmd)
+			if err := calc.Eval(tt.cmd); err != nil {
+				t.Errorf(err.Error())
+			}
 			got := calc.Result()
 			calc.stack.Clear()
 			if got != tt.exp {
@@ -350,3 +356,60 @@ func TestCalcLua(t *testing.T) {
 		})
 	}
 }
+
+func FuzzEval(f *testing.F) {
+	legal := []string{
+		"dump",
+		"showstack",
+		"help",
+		"Pi 31 *",
+		"SqrtE Pi /",
+		"55.5 yards-to-meters",
+		"2 4 +",
+		"7 8 batch sum",
+		"7 8 %-",
+		"7 8 clear",
+		"7 8 /",
+		"b",
+		"#444",
+		"<X",
+	}
+
+	for _, item := range legal {
+		f.Add(item)
+	}
+
+	calc := NewCalc()
+	var i int
+
+	f.Fuzz(func(t *testing.T, line string) {
+		t.Logf("Stack:\n%v\n", calc.stack.All())
+		if err := calc.EvalItem(line); err == nil {
+			t.Logf("given: <%s>", line)
+			// not corpus and empty?
+			if !contains(legal, line) && len(line) > 0 {
+				item := strings.TrimSpace(calc.Comment.ReplaceAllString(line, ""))
+				_, hexerr := fmt.Sscanf(item, "0x%x", &i)
+				// no comment?
+				if len(item) > 0 {
+					// no known command or function?
+					if _, err := strconv.ParseFloat(item, 64); err != nil {
+						if !contains(calc.Constants, item) &&
+							!exists(calc.Funcalls, item) &&
+							!exists(calc.BatchFuncalls, item) &&
+							!contains(calc.LuaFunctions, item) &&
+							!exists(calc.Commands, item) &&
+							!exists(calc.ShowCommands, item) &&
+							!exists(calc.SettingsCommands, item) &&
+							!exists(calc.StackCommands, item) &&
+							!calc.Register.MatchString(item) &&
+							item != "?" && item != "help" &&
+							hexerr != nil {
+							t.Errorf("Fuzzy input accepted: <%s>", line)
+						}
+					}
+				}
+			}
+		}
+	})
+}

funcs.go

@@ -457,12 +457,20 @@ func DefineFunctions() Funcalls {
 
 		"<": NewFuncall(
 			func(arg Numbers) R {
+				// Shift by negative number provibited, so check it.
+				// Note that we check agains uint64 overflow as well here
+				if arg[1] < 0 || uint64(arg[1]) > math.MaxInt64 {
+					return NewR(0, errors.New("negative shift amount"))
+				}
 				return NewR(float64(int(arg[0])<<int(arg[1])), nil)
 			},
 			2),
 
 		">": NewFuncall(
 			func(arg Numbers) R {
+				if arg[1] < 0 || uint64(arg[1]) > math.MaxInt64 {
+					return NewR(0, errors.New("negative shift amount"))
+				}
 				return NewR(float64(int(arg[0])>>int(arg[1])), nil)
 			},
 			2),