Ensure context lookups traverse lineage

Closes #487

context_test.go

@@ -35,57 +35,89 @@ func TestNewContext(t *testing.T) {
 func TestContext_Int(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Int("myflag", 12, "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.Int("top-flag", 13, "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.Int("myflag"), 12)
+	expect(t, c.Int("top-flag"), 13)
 }
 
 func TestContext_Int64(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Int64("myflagInt64", 12, "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.Int64("top-flag", 13, "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.Int64("myflagInt64"), int64(12))
+	expect(t, c.Int64("top-flag"), int64(13))
 }
 
 func TestContext_Uint(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Uint("myflagUint", uint(13), "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.Uint("top-flag", uint(14), "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.Uint("myflagUint"), uint(13))
+	expect(t, c.Uint("top-flag"), uint(14))
 }
 
 func TestContext_Uint64(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Uint64("myflagUint64", uint64(9), "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.Uint64("top-flag", uint64(10), "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.Uint64("myflagUint64"), uint64(9))
+	expect(t, c.Uint64("top-flag"), uint64(10))
 }
 
 func TestContext_Float64(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Float64("myflag", float64(17), "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.Float64("top-flag", float64(18), "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.Float64("myflag"), float64(17))
+	expect(t, c.Float64("top-flag"), float64(18))
 }
 
 func TestContext_Duration(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
-	set.Duration("myflag", time.Duration(12*time.Second), "doc")
+	set.Duration("myflag", 12*time.Second, "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
-	expect(t, c.Duration("myflag"), time.Duration(12*time.Second))
+	parentSet.Duration("top-flag", 13*time.Second, "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
+	expect(t, c.Duration("myflag"), 12*time.Second)
+	expect(t, c.Duration("top-flag"), 13*time.Second)
 }
 
 func TestContext_String(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.String("myflag", "hello world", "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.String("top-flag", "hai veld", "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.String("myflag"), "hello world")
+	expect(t, c.String("top-flag"), "hai veld")
 }
 
 func TestContext_Bool(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Bool("myflag", false, "doc")
-	c := NewContext(nil, set, nil)
+	parentSet := flag.NewFlagSet("test", 0)
+	parentSet.Bool("top-flag", true, "doc")
+	parentCtx := NewContext(nil, parentSet, nil)
+	c := NewContext(nil, set, parentCtx)
 	expect(t, c.Bool("myflag"), false)
+	expect(t, c.Bool("top-flag"), true)
 }
 
 func TestContext_Args(t *testing.T) {

flag_generated.go

@@ -33,7 +33,10 @@ func (f *BoolFlag) Names() []string {
 // Bool looks up the value of a local BoolFlag, returns
 // false if not found
 func (c *Context) Bool(name string) bool {
-	return lookupBool(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupBool(name, fs)
+	}
+	return false
 }
 
 func lookupBool(name string, set *flag.FlagSet) bool {
@@ -73,7 +76,10 @@ func (f *DurationFlag) Names() []string {
 // Duration looks up the value of a local DurationFlag, returns
 // 0 if not found
 func (c *Context) Duration(name string) time.Duration {
-	return lookupDuration(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupDuration(name, fs)
+	}
+	return 0
 }
 
 func lookupDuration(name string, set *flag.FlagSet) time.Duration {
@@ -113,7 +119,10 @@ func (f *Float64Flag) Names() []string {
 // Float64 looks up the value of a local Float64Flag, returns
 // 0 if not found
 func (c *Context) Float64(name string) float64 {
-	return lookupFloat64(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupFloat64(name, fs)
+	}
+	return 0
 }
 
 func lookupFloat64(name string, set *flag.FlagSet) float64 {
@@ -152,7 +161,10 @@ func (f *GenericFlag) Names() []string {
 // Generic looks up the value of a local GenericFlag, returns
 // nil if not found
 func (c *Context) Generic(name string) interface{} {
-	return lookupGeneric(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupGeneric(name, fs)
+	}
+	return nil
 }
 
 func lookupGeneric(name string, set *flag.FlagSet) interface{} {
@@ -192,7 +204,10 @@ func (f *Int64Flag) Names() []string {
 // Int64 looks up the value of a local Int64Flag, returns
 // 0 if not found
 func (c *Context) Int64(name string) int64 {
-	return lookupInt64(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupInt64(name, fs)
+	}
+	return 0
 }
 
 func lookupInt64(name string, set *flag.FlagSet) int64 {
@@ -232,7 +247,10 @@ func (f *IntFlag) Names() []string {
 // Int looks up the value of a local IntFlag, returns
 // 0 if not found
 func (c *Context) Int(name string) int {
-	return lookupInt(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupInt(name, fs)
+	}
+	return 0
 }
 
 func lookupInt(name string, set *flag.FlagSet) int {
@@ -271,7 +289,10 @@ func (f *IntSliceFlag) Names() []string {
 // IntSlice looks up the value of a local IntSliceFlag, returns
 // nil if not found
 func (c *Context) IntSlice(name string) []int {
-	return lookupIntSlice(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupIntSlice(name, fs)
+	}
+	return nil
 }
 
 func lookupIntSlice(name string, set *flag.FlagSet) []int {
@@ -310,7 +331,10 @@ func (f *Int64SliceFlag) Names() []string {
 // Int64Slice looks up the value of a local Int64SliceFlag, returns
 // nil if not found
 func (c *Context) Int64Slice(name string) []int64 {
-	return lookupInt64Slice(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupInt64Slice(name, fs)
+	}
+	return nil
 }
 
 func lookupInt64Slice(name string, set *flag.FlagSet) []int64 {
@@ -349,7 +373,10 @@ func (f *Float64SliceFlag) Names() []string {
 // Float64Slice looks up the value of a local Float64SliceFlag, returns
 // nil if not found
 func (c *Context) Float64Slice(name string) []float64 {
-	return lookupFloat64Slice(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupFloat64Slice(name, fs)
+	}
+	return nil
 }
 
 func lookupFloat64Slice(name string, set *flag.FlagSet) []float64 {
@@ -389,7 +416,10 @@ func (f *StringFlag) Names() []string {
 // String looks up the value of a local StringFlag, returns
 // "" if not found
 func (c *Context) String(name string) string {
-	return lookupString(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupString(name, fs)
+	}
+	return ""
 }
 
 func lookupString(name string, set *flag.FlagSet) string {
@@ -428,7 +458,10 @@ func (f *StringSliceFlag) Names() []string {
 // StringSlice looks up the value of a local StringSliceFlag, returns
 // nil if not found
 func (c *Context) StringSlice(name string) []string {
-	return lookupStringSlice(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupStringSlice(name, fs)
+	}
+	return nil
 }
 
 func lookupStringSlice(name string, set *flag.FlagSet) []string {
@@ -468,7 +501,10 @@ func (f *Uint64Flag) Names() []string {
 // Uint64 looks up the value of a local Uint64Flag, returns
 // 0 if not found
 func (c *Context) Uint64(name string) uint64 {
-	return lookupUint64(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupUint64(name, fs)
+	}
+	return 0
 }
 
 func lookupUint64(name string, set *flag.FlagSet) uint64 {
@@ -508,7 +544,10 @@ func (f *UintFlag) Names() []string {
 // Uint looks up the value of a local UintFlag, returns
 // 0 if not found
 func (c *Context) Uint(name string) uint {
-	return lookupUint(name, c.flagSet)
+	if fs := lookupFlagSet(name, c); fs != nil {
+		return lookupUint(name, fs)
+	}
+	return 0
 }
 
 func lookupUint(name string, set *flag.FlagSet) uint {

generate-flag-types

@@ -169,7 +169,10 @@ def _write_cli_flag_types(outfile, types):
             // {name} looks up the value of a local {name}Flag, returns
             // {context_default} if not found
             func (c *Context) {name}(name string) {context_type} {{
-                return lookup{name}(name, c.flagSet)
+                if fs := lookupFlagSet(name, c); fs != nil {{
+                    return lookup{name}(name, fs)
+                }}
+                return {context_default}
             }}
 
             func lookup{name}(name string, set *flag.FlagSet) {context_type} {{