Add Context.GlobalFloat64 plus tests

Closes #362

context.go

@@ -79,6 +79,15 @@ func (c *Context) GlobalInt(name string) int {
 	return 0
 }
 
+// Looks up the value of a global float64 flag, returns float64(0) if no float64
+// flag exists
+func (c *Context) GlobalFloat64(name string) float64 {
+	if fs := lookupGlobalFlagSet(name, c); fs != nil {
+		return lookupFloat64(name, fs)
+	}
+	return float64(0)
+}
+
 // Looks up the value of a global time.Duration flag, returns 0 if no time.Duration flag exists
 func (c *Context) GlobalDuration(name string) time.Duration {
 	if fs := lookupGlobalFlagSet(name, c); fs != nil {

context_test.go

@@ -9,14 +9,18 @@ import (
 func TestNewContext(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Int("myflag", 12, "doc")
+	set.Float64("myflag64", float64(17), "doc")
 	globalSet := flag.NewFlagSet("test", 0)
 	globalSet.Int("myflag", 42, "doc")
+	globalSet.Float64("myflag64", float64(47), "doc")
 	globalCtx := NewContext(nil, globalSet, nil)
 	command := Command{Name: "mycommand"}
 	c := NewContext(nil, set, globalCtx)
 	c.Command = command
 	expect(t, c.Int("myflag"), 12)
+	expect(t, c.Float64("myflag64"), float64(17))
 	expect(t, c.GlobalInt("myflag"), 42)
+	expect(t, c.GlobalFloat64("myflag64"), float64(47))
 	expect(t, c.Command.Name, "mycommand")
 }
 
@@ -27,6 +31,29 @@ func TestContext_Int(t *testing.T) {
 	expect(t, c.Int("myflag"), 12)
 }
 
+func TestContext_GlobalInt(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Int("myflag", 12, "doc")
+	c := NewContext(nil, set, nil)
+	expect(t, c.GlobalInt("myflag"), 12)
+	expect(t, c.GlobalInt("nope"), 0)
+}
+
+func TestContext_Float64(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Float64("myflag", float64(17), "doc")
+	c := NewContext(nil, set, nil)
+	expect(t, c.Float64("myflag"), float64(17))
+}
+
+func TestContext_GlobalFloat64(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Float64("myflag", float64(17), "doc")
+	c := NewContext(nil, set, nil)
+	expect(t, c.GlobalFloat64("myflag"), float64(17))
+	expect(t, c.GlobalFloat64("nope"), float64(0))
+}
+
 func TestContext_Duration(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Duration("myflag", time.Duration(12*time.Second), "doc")