Avoids that the rc crashes when encountering more than one package

in the same directory

go/tests/rc/rc.go

@@ -279,6 +279,14 @@ func loadProgram(path string, load loadedSource) error {
 		return err
 	}
 
+	if len(pkgs) > 1 {
+		packages := []string{}
+		for pkgName := range pkgs {
+			packages = append(packages, pkgName)
+		}
+		return fmt.Errorf("There should be only one package in this directory: Found packages: %v", packages)
+	}
+
 	for _, pkg := range pkgs {
 		ast.Walk(l, pkg)
 		l.pkgScope = ast.NewScope(nil)
@@ -779,6 +787,14 @@ type loadVisitor struct {
 	files    map[string]*ast.File
 }
 
+func (l *loadVisitor) String() (res string) {
+	res = "files"
+	for f, _ := range l.files {
+		res += f + ","
+	}
+	return res
+}
+
 // Returns all the parameter of a function that identify a function
 func functionsInTheParameters(params *ast.FieldList) []string {
 	var funcs []string

go/tests/rc/tests/grand-prix-go-burdeux/isnegative.go

@@ -0,0 +1,11 @@
+package piscine
+
+import "github.com/01-edu/z01"
+
+func IsNegative(nb int) {
+	if nb < 0 {
+		z01.PrintRune('T')
+	} else {
+		z01.PrintRune('F')
+	}
+}

go/tests/rc/tests/moreThanOnePackage/func.go

@@ -0,0 +1,5 @@
+package piscine
+
+func hello() {
+	println("Nothing here")
+}

go/tests/rc/tests/moreThanOnePackage/main.go

@@ -0,0 +1,7 @@
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("Hello world")
+}

go/tests/rc/tests/testLiteralRestriction/main.go

@@ -0,0 +1,10 @@
+package main
+
+import "github.com/01-edu/z01"
+
+func main() {
+	alphabet := "abcdefghijklmnopqrstuvwxyz\n"
+	for _, letter := range alphabet {
+		z01.PrintRune(letter)
+	}
+}