From 27f53db0f44855b64423dc18b918d8fe576b7e5e Mon Sep 17 00:00:00 2001
From: Celestino Amoroso <celestino.amoroso@gmail.com>
Date: Thu, 28 Mar 2024 06:33:14 +0100
Subject: [PATCH] helpers_test.go: tests on the helper functions

---
 helpers_test.go | 80 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)
 create mode 100644 helpers_test.go

diff --git a/helpers_test.go b/helpers_test.go
new file mode 100644
index 0000000..daa40c3
--- /dev/null
+++ b/helpers_test.go
@@ -0,0 +1,80 @@
+// helpers_test.go
+package expr
+
+import (
+	"fmt"
+	"testing"
+)
+
+func subtract(ctx exprContext, name string, args []any) (result any, err error) {
+	if len(args) != 2 {
+		err = fmt.Errorf("%s(): requires exactly two arguments", name)
+		return
+	}
+	x, xok := args[0].(int64)
+	y, yok := args[1].(int64)
+	if xok && yok {
+		result = x - y
+	} else {
+		err = fmt.Errorf("expected integer (int64) arguments, got %T and %T values", x, y)
+	}
+	return
+}
+
+func TestEvalStringA(t *testing.T) {
+
+	source := `a + b * subtract(4,2)`
+	args := []EvalArg{
+		{"a", uint8(1)},
+		{"b", int8(2)},
+		{"subtract", FuncTemplate(subtract)},
+		// enforce coverage
+		{"a16", uint16(1)},
+		{"b16", int16(2)},
+		{"a32", uint32(1)},
+		{"b32", int32(2)},
+		{"a64", uint64(1)},
+		{"b64", int64(2)},
+		{"f32", float32(1.0)},
+		{"f64", float64(1.0)},
+	}
+
+	wantResult := int64(5)
+	gotResult, gotErr := EvalStringA(source, args...)
+	if value, ok := gotResult.(int64); ok && value != wantResult {
+		t.Errorf("Source %q got %v, want %v", source, gotResult, wantResult)
+		t.Errorf("Error: %v", gotErr)
+	}
+	fmt.Println("Hello World!")
+}
+
+func TestEvalString(t *testing.T) {
+
+	ctx := NewSimpleVarStore()
+	ctx.SetValue("a", uint8(1))
+	ctx.SetValue("b", int8(2))
+	ctx.SetValue("f", 2.0)
+	// enforce coverage
+	ctx.SetValue("a16", uint16(1))
+	ctx.SetValue("b16", int16(2))
+	ctx.SetValue("a32", uint32(1))
+	ctx.SetValue("b32", int32(2))
+	ctx.SetValue("a64", uint64(1))
+	ctx.SetValue("b64", int64(2))
+	ctx.SetValue("f32", float32(1.0))
+	ctx.SetValue("f64", float64(1.0))
+
+	// enforce coverage
+	ctx.GetFuncInfo("dummy")
+	ctx.Call("dummy", []any{})
+
+	source := `a + b * f`
+
+	wantResult := float64(5)
+	gotResult, gotErr := EvalString(ctx, source)
+	if value, ok := gotResult.(float64); ok && value != wantResult {
+		t.Errorf("Source %q got %v, want %v", source, gotResult, wantResult)
+		t.Errorf("Error: %v", gotErr)
+	}
+	fmt.Println("Hello World!")
+}