diff --git a/altsrc.go b/altsrc.go
deleted file mode 100644
index ac34bf6..0000000
--- a/altsrc.go
+++ /dev/null
@@ -1,3 +0,0 @@
-package altsrc
-
-//go:generate python ../generate-flag-types altsrc -i ../flag-types.json -o flag_generated.go
diff --git a/flag.go b/flag.go
index 858e54e..31b8a04 100644
--- a/flag.go
+++ b/flag.go
@@ -6,7 +6,7 @@ import (
 	"strconv"
 	"syscall"
 
-	"gopkg.in/urfave/cli.v2"
+	"github.com/urfave/cli/v2"
 )
 
 // FlagInputSourceExtension is an extension interface of cli.Flag that
@@ -72,7 +72,7 @@ func (f *GenericFlag) ApplyInputSourceValue(context *cli.Context, isc InputSourc
 			}
 			if value != nil {
 				for _, name := range f.Names() {
-					f.set.Set(name, value.String())
+					_ = f.set.Set(name, value.String())
 				}
 			}
 		}
@@ -135,7 +135,7 @@ func (f *BoolFlag) ApplyInputSourceValue(context *cli.Context, isc InputSourceCo
 			}
 			if value {
 				for _, name := range f.Names() {
-					f.set.Set(name, strconv.FormatBool(value))
+					_ = f.set.Set(name, strconv.FormatBool(value))
 				}
 			}
 		}
@@ -153,7 +153,7 @@ func (f *StringFlag) ApplyInputSourceValue(context *cli.Context, isc InputSource
 			}
 			if value != "" {
 				for _, name := range f.Names() {
-					f.set.Set(name, value)
+					_ = f.set.Set(name, value)
 				}
 			}
 		}
@@ -181,7 +181,7 @@ func (f *PathFlag) ApplyInputSourceValue(context *cli.Context, isc InputSourceCo
 						value = filepath.Join(filepath.Dir(basePathAbs), value)
 					}
 
-					f.set.Set(name, value)
+					_ = f.set.Set(name, value)
 				}
 			}
 		}
@@ -199,7 +199,7 @@ func (f *IntFlag) ApplyInputSourceValue(context *cli.Context, isc InputSourceCon
 			}
 			if value > 0 {
 				for _, name := range f.Names() {
-					f.set.Set(name, strconv.FormatInt(int64(value), 10))
+					_ = f.set.Set(name, strconv.FormatInt(int64(value), 10))
 				}
 			}
 		}
@@ -217,7 +217,7 @@ func (f *DurationFlag) ApplyInputSourceValue(context *cli.Context, isc InputSour
 			}
 			if value > 0 {
 				for _, name := range f.Names() {
-					f.set.Set(name, value.String())
+					_ = f.set.Set(name, value.String())
 				}
 			}
 		}
@@ -236,7 +236,7 @@ func (f *Float64Flag) ApplyInputSourceValue(context *cli.Context, isc InputSourc
 			if value > 0 {
 				floatStr := float64ToString(value)
 				for _, name := range f.Names() {
-					f.set.Set(name, floatStr)
+					_ = f.set.Set(name, floatStr)
 				}
 			}
 		}
diff --git a/flag_generated.go b/flag_generated.go
index 87c7c5d..de3e2b5 100644
--- a/flag_generated.go
+++ b/flag_generated.go
@@ -2,12 +2,9 @@ package altsrc
 
 import (
 	"flag"
-
-	"gopkg.in/urfave/cli.v2"
+	"github.com/urfave/cli/v2"
 )
 
-// WARNING: This file is generated!
-
 // BoolFlag is the flag type that wraps cli.BoolFlag to allow
 // for other values to be specified
 type BoolFlag struct {
@@ -20,18 +17,11 @@ func NewBoolFlag(fl *cli.BoolFlag) *BoolFlag {
 	return &BoolFlag{BoolFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped BoolFlag.Apply
-func (f *BoolFlag) Apply(set *flag.FlagSet) {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped BoolFlag.Apply
+func (f *BoolFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	f.BoolFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped BoolFlag.ApplyWithError
-func (f *BoolFlag) ApplyWithError(set *flag.FlagSet) error {
-	f.set = set
-	return f.BoolFlag.ApplyWithError(set)
+	return f.BoolFlag.Apply(set)
 }
 
 // DurationFlag is the flag type that wraps cli.DurationFlag to allow
@@ -46,18 +36,11 @@ func NewDurationFlag(fl *cli.DurationFlag) *DurationFlag {
 	return &DurationFlag{DurationFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped DurationFlag.Apply
-func (f *DurationFlag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.DurationFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped DurationFlag.ApplyWithError
-func (f *DurationFlag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped DurationFlag.Apply
+func (f *DurationFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.DurationFlag.ApplyWithError(set)
+	return f.DurationFlag.Apply(set)
 }
 
 // Float64Flag is the flag type that wraps cli.Float64Flag to allow
@@ -72,18 +55,11 @@ func NewFloat64Flag(fl *cli.Float64Flag) *Float64Flag {
 	return &Float64Flag{Float64Flag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped Float64Flag.Apply
-func (f *Float64Flag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.Float64Flag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped Float64Flag.ApplyWithError
-func (f *Float64Flag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped Float64Flag.Apply
+func (f *Float64Flag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.Float64Flag.ApplyWithError(set)
+	return f.Float64Flag.Apply(set)
 }
 
 // GenericFlag is the flag type that wraps cli.GenericFlag to allow
@@ -98,18 +74,11 @@ func NewGenericFlag(fl *cli.GenericFlag) *GenericFlag {
 	return &GenericFlag{GenericFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped GenericFlag.Apply
-func (f *GenericFlag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.GenericFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped GenericFlag.ApplyWithError
-func (f *GenericFlag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped GenericFlag.Apply
+func (f *GenericFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.GenericFlag.ApplyWithError(set)
+	return f.GenericFlag.Apply(set)
 }
 
 // Int64Flag is the flag type that wraps cli.Int64Flag to allow
@@ -124,18 +93,11 @@ func NewInt64Flag(fl *cli.Int64Flag) *Int64Flag {
 	return &Int64Flag{Int64Flag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped Int64Flag.Apply
-func (f *Int64Flag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.Int64Flag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped Int64Flag.ApplyWithError
-func (f *Int64Flag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped Int64Flag.Apply
+func (f *Int64Flag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.Int64Flag.ApplyWithError(set)
+	return f.Int64Flag.Apply(set)
 }
 
 // IntFlag is the flag type that wraps cli.IntFlag to allow
@@ -150,18 +112,11 @@ func NewIntFlag(fl *cli.IntFlag) *IntFlag {
 	return &IntFlag{IntFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped IntFlag.Apply
-func (f *IntFlag) Apply(set *flag.FlagSet) {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped IntFlag.Apply
+func (f *IntFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	f.IntFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped IntFlag.ApplyWithError
-func (f *IntFlag) ApplyWithError(set *flag.FlagSet) error {
-	f.set = set
-	return f.IntFlag.ApplyWithError(set)
+	return f.IntFlag.Apply(set)
 }
 
 // IntSliceFlag is the flag type that wraps cli.IntSliceFlag to allow
@@ -176,18 +131,11 @@ func NewIntSliceFlag(fl *cli.IntSliceFlag) *IntSliceFlag {
 	return &IntSliceFlag{IntSliceFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped IntSliceFlag.Apply
-func (f *IntSliceFlag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.IntSliceFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped IntSliceFlag.ApplyWithError
-func (f *IntSliceFlag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped IntSliceFlag.Apply
+func (f *IntSliceFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.IntSliceFlag.ApplyWithError(set)
+	return f.IntSliceFlag.Apply(set)
 }
 
 // Int64SliceFlag is the flag type that wraps cli.Int64SliceFlag to allow
@@ -202,18 +150,11 @@ func NewInt64SliceFlag(fl *cli.Int64SliceFlag) *Int64SliceFlag {
 	return &Int64SliceFlag{Int64SliceFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped Int64SliceFlag.Apply
-func (f *Int64SliceFlag) Apply(set *flag.FlagSet) {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped Int64SliceFlag.Apply
+func (f *Int64SliceFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	f.Int64SliceFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped Int64SliceFlag.ApplyWithError
-func (f *Int64SliceFlag) ApplyWithError(set *flag.FlagSet) error {
-	f.set = set
-	return f.Int64SliceFlag.ApplyWithError(set)
+	return f.Int64SliceFlag.Apply(set)
 }
 
 // Float64SliceFlag is the flag type that wraps cli.Float64SliceFlag to allow
@@ -230,16 +171,9 @@ func NewFloat64SliceFlag(fl *cli.Float64SliceFlag) *Float64SliceFlag {
 
 // Apply saves the flagSet for later usage calls, then calls the
 // wrapped Float64SliceFlag.Apply
-func (f *Float64SliceFlag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.Float64SliceFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped Float64SliceFlag.ApplyWithError
-func (f *Float64SliceFlag) ApplyWithError(set *flag.FlagSet) error {
+func (f *Float64SliceFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.Float64SliceFlag.ApplyWithError(set)
+	return f.Float64SliceFlag.Apply(set)
 }
 
 // StringFlag is the flag type that wraps cli.StringFlag to allow
@@ -254,18 +188,11 @@ func NewStringFlag(fl *cli.StringFlag) *StringFlag {
 	return &StringFlag{StringFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped StringFlag.Apply
-func (f *StringFlag) Apply(set *flag.FlagSet) {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped StringFlag.Apply
+func (f *StringFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	f.StringFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped StringFlag.ApplyWithError
-func (f *StringFlag) ApplyWithError(set *flag.FlagSet) error {
-	f.set = set
-	return f.StringFlag.ApplyWithError(set)
+	return f.StringFlag.Apply(set)
 }
 
 // PathFlag is the flag type that wraps cli.PathFlag to allow
@@ -282,16 +209,9 @@ func NewPathFlag(fl *cli.PathFlag) *PathFlag {
 
 // Apply saves the flagSet for later usage calls, then calls the
 // wrapped PathFlag.Apply
-func (f *PathFlag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.PathFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped PathFlag.ApplyWithError
-func (f *PathFlag) ApplyWithError(set *flag.FlagSet) error {
+func (f *PathFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.PathFlag.ApplyWithError(set)
+	return f.PathFlag.Apply(set)
 }
 
 // StringSliceFlag is the flag type that wraps cli.StringSliceFlag to allow
@@ -306,18 +226,11 @@ func NewStringSliceFlag(fl *cli.StringSliceFlag) *StringSliceFlag {
 	return &StringSliceFlag{StringSliceFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped StringSliceFlag.Apply
-func (f *StringSliceFlag) Apply(set *flag.FlagSet) {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped StringSliceFlag.Apply
+func (f *StringSliceFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	f.StringSliceFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped StringSliceFlag.ApplyWithError
-func (f *StringSliceFlag) ApplyWithError(set *flag.FlagSet) error {
-	f.set = set
-	return f.StringSliceFlag.ApplyWithError(set)
+	return f.StringSliceFlag.Apply(set)
 }
 
 // Uint64Flag is the flag type that wraps cli.Uint64Flag to allow
@@ -332,18 +245,11 @@ func NewUint64Flag(fl *cli.Uint64Flag) *Uint64Flag {
 	return &Uint64Flag{Uint64Flag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped Uint64Flag.Apply
-func (f *Uint64Flag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.Uint64Flag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped Uint64Flag.ApplyWithError
-func (f *Uint64Flag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped Uint64Flag.Apply
+func (f *Uint64Flag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.Uint64Flag.ApplyWithError(set)
+	return f.Uint64Flag.Apply(set)
 }
 
 // UintFlag is the flag type that wraps cli.UintFlag to allow
@@ -358,16 +264,9 @@ func NewUintFlag(fl *cli.UintFlag) *UintFlag {
 	return &UintFlag{UintFlag: fl, set: nil}
 }
 
-// Apply saves the flagSet for later usage calls, then calls the
-// wrapped UintFlag.Apply
-func (f *UintFlag) Apply(set *flag.FlagSet) {
-	f.set = set
-	f.UintFlag.Apply(set)
-}
-
-// ApplyWithError saves the flagSet for later usage calls, then calls the
-// wrapped UintFlag.ApplyWithError
-func (f *UintFlag) ApplyWithError(set *flag.FlagSet) error {
+// Apply saves the flagSet for later usage calls, then calls
+// the wrapped UintFlag.Apply
+func (f *UintFlag) Apply(set *flag.FlagSet) error {
 	f.set = set
-	return f.UintFlag.ApplyWithError(set)
+	return f.UintFlag.Apply(set)
 }
diff --git a/flag_test.go b/flag_test.go
index 087e607..b5fcbf5 100644
--- a/flag_test.go
+++ b/flag_test.go
@@ -3,13 +3,12 @@ package altsrc
 import (
 	"flag"
 	"fmt"
+	"github.com/urfave/cli/v2"
 	"os"
 	"runtime"
 	"strings"
 	"testing"
 	"time"
-
-	"gopkg.in/urfave/cli.v2"
 )
 
 type testApplyInputSource struct {
@@ -252,30 +251,30 @@ func TestDurationApplyInputSourceMethodSet(t *testing.T) {
 	c := runTest(t, testApplyInputSource{
 		Flag:     NewDurationFlag(&cli.DurationFlag{Name: "test"}),
 		FlagName: "test",
-		MapValue: time.Duration(30 * time.Second),
+		MapValue: 30 * time.Second,
 	})
-	expect(t, time.Duration(30*time.Second), c.Duration("test"))
+	expect(t, 30*time.Second, c.Duration("test"))
 }
 
 func TestDurationApplyInputSourceMethodContextSet(t *testing.T) {
 	c := runTest(t, testApplyInputSource{
 		Flag:               NewDurationFlag(&cli.DurationFlag{Name: "test"}),
 		FlagName:           "test",
-		MapValue:           time.Duration(30 * time.Second),
-		ContextValueString: time.Duration(15 * time.Second).String(),
+		MapValue:           30 * time.Second,
+		ContextValueString: (15 * time.Second).String(),
 	})
-	expect(t, time.Duration(15*time.Second), c.Duration("test"))
+	expect(t, 15*time.Second, c.Duration("test"))
 }
 
 func TestDurationApplyInputSourceMethodEnvVarSet(t *testing.T) {
 	c := runTest(t, testApplyInputSource{
 		Flag:        NewDurationFlag(&cli.DurationFlag{Name: "test", EnvVars: []string{"TEST"}}),
 		FlagName:    "test",
-		MapValue:    time.Duration(30 * time.Second),
+		MapValue:    30 * time.Second,
 		EnvVarName:  "TEST",
-		EnvVarValue: time.Duration(15 * time.Second).String(),
+		EnvVarValue: (15 * time.Second).String(),
 	})
-	expect(t, time.Duration(15*time.Second), c.Duration("test"))
+	expect(t, 15*time.Second, c.Duration("test"))
 }
 
 func TestFloat64ApplyInputSourceMethodSet(t *testing.T) {
@@ -316,19 +315,19 @@ func runTest(t *testing.T, test testApplyInputSource) *cli.Context {
 	set := flag.NewFlagSet(test.FlagSetName, flag.ContinueOnError)
 	c := cli.NewContext(nil, set, nil)
 	if test.EnvVarName != "" && test.EnvVarValue != "" {
-		os.Setenv(test.EnvVarName, test.EnvVarValue)
+		_ = os.Setenv(test.EnvVarName, test.EnvVarValue)
 		defer os.Setenv(test.EnvVarName, "")
 	}
 
 	test.Flag.Apply(set)
 	if test.ContextValue != nil {
-		flag := set.Lookup(test.FlagName)
-		flag.Value = test.ContextValue
+		f := set.Lookup(test.FlagName)
+		f.Value = test.ContextValue
 	}
 	if test.ContextValueString != "" {
-		set.Set(test.FlagName, test.ContextValueString)
+		_ = set.Set(test.FlagName, test.ContextValueString)
 	}
-	test.Flag.ApplyInputSourceValue(c, inputSource)
+	_ = test.Flag.ApplyInputSourceValue(c, inputSource)
 
 	return c
 }
diff --git a/input_source_context.go b/input_source_context.go
index bb0afdb..5f60574 100644
--- a/input_source_context.go
+++ b/input_source_context.go
@@ -1,9 +1,8 @@
 package altsrc
 
 import (
+	"github.com/urfave/cli/v2"
 	"time"
-
-	"gopkg.in/urfave/cli.v2"
 )
 
 // InputSourceContext is an interface used to allow
diff --git a/json_command_test.go b/json_command_test.go
index ccb5041..bd8e6cf 100644
--- a/json_command_test.go
+++ b/json_command_test.go
@@ -2,11 +2,10 @@ package altsrc
 
 import (
 	"flag"
+	"github.com/urfave/cli/v2"
 	"io/ioutil"
 	"os"
 	"testing"
-
-	"gopkg.in/urfave/cli.v2"
 )
 
 const (
@@ -22,7 +21,7 @@ func TestCommandJSONFileTest(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -52,11 +51,11 @@ func TestCommandJSONFileTestGlobalEnvVarWins(t *testing.T) {
 
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	os.Setenv("THE_TEST", "10")
+	_ = os.Setenv("THE_TEST", "10")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -87,11 +86,11 @@ func TestCommandJSONFileTestGlobalEnvVarWinsNested(t *testing.T) {
 
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	os.Setenv("THE_TEST", "10")
+	_ = os.Setenv("THE_TEST", "10")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -123,7 +122,7 @@ func TestCommandJSONFileTestSpecifiedFlagWins(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
 	test := []string{"test-cmd", "--load", fileName, "--test", "7"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -155,7 +154,7 @@ func TestCommandJSONFileTestSpecifiedFlagWinsNested(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
 	test := []string{"test-cmd", "--load", fileName, "--top.test", "7"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -187,7 +186,7 @@ func TestCommandJSONFileTestDefaultValueFileWins(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -219,7 +218,7 @@ func TestCommandJSONFileTestDefaultValueFileWinsNested(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -250,11 +249,11 @@ func TestCommandJSONFileFlagHasDefaultGlobalEnvJSONSetGlobalEnvWins(t *testing.T
 
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	os.Setenv("THE_TEST", "11")
+	_ = os.Setenv("THE_TEST", "11")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -284,11 +283,11 @@ func TestCommandJSONFileFlagHasDefaultGlobalEnvJSONSetGlobalEnvWinsNested(t *tes
 
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	os.Setenv("THE_TEST", "11")
+	_ = os.Setenv("THE_TEST", "11")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", fileName}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
diff --git a/json_source_context.go b/json_source_context.go
index 34c7eb9..41602ad 100644
--- a/json_source_context.go
+++ b/json_source_context.go
@@ -3,12 +3,11 @@ package altsrc
 import (
 	"encoding/json"
 	"fmt"
+	"github.com/urfave/cli/v2"
 	"io"
 	"io/ioutil"
 	"strings"
 	"time"
-
-	"gopkg.in/urfave/cli.v2"
 )
 
 // NewJSONSourceFromFlagFunc returns a func that takes a cli.Context
@@ -29,13 +28,8 @@ func NewJSONSourceFromFile(f string) (InputSourceContext, error) {
 	if err != nil {
 		return nil, err
 	}
-	s, err := newJSONSource(data)
-	if err != nil {
-		return nil, err
-	}
 
-	s.file = f
-	return s, nil
+	return NewJSONSource(data)
 }
 
 // NewJSONSourceFromReader returns an InputSourceContext suitable for
@@ -51,10 +45,6 @@ func NewJSONSourceFromReader(r io.Reader) (InputSourceContext, error) {
 // NewJSONSource returns an InputSourceContext suitable for retrieving
 // config variables from raw JSON data.
 func NewJSONSource(data []byte) (InputSourceContext, error) {
-	return newJSONSource(data)
-}
-
-func newJSONSource(data []byte) (*jsonSource, error) {
 	var deserialized map[string]interface{}
 	if err := json.Unmarshal(data, &deserialized); err != nil {
 		return nil, err
@@ -77,9 +67,9 @@ func (x *jsonSource) Int(name string) (int, error) {
 	case int:
 		return v, nil
 	case float64:
-		return int(float64(v)), nil
+		return int(v), nil
 	case float32:
-		return int(float32(v)), nil
+		return int(v), nil
 	}
 }
 
diff --git a/map_input_source.go b/map_input_source.go
index 41221b1..66bd6e8 100644
--- a/map_input_source.go
+++ b/map_input_source.go
@@ -2,11 +2,10 @@ package altsrc
 
 import (
 	"fmt"
+	"github.com/urfave/cli/v2"
 	"reflect"
 	"strings"
 	"time"
-
-	"gopkg.in/urfave/cli.v2"
 )
 
 // MapInputSource implements InputSourceContext to return
@@ -23,15 +22,15 @@ func nestedVal(name string, tree map[interface{}]interface{}) (interface{}, bool
 	if sections := strings.Split(name, "."); len(sections) > 1 {
 		node := tree
 		for _, section := range sections[:len(sections)-1] {
-			if child, ok := node[section]; !ok {
+			child, ok := node[section]
+			if !ok {
+				return nil, false
+			}
+			ctype, ok := child.(map[interface{}]interface{})
+			if !ok {
 				return nil, false
-			} else {
-				if ctype, ok := child.(map[interface{}]interface{}); !ok {
-					return nil, false
-				} else {
-					node = ctype
-				}
 			}
+			node = ctype
 		}
 		if val, ok := node[sections[len(sections)-1]]; ok {
 			return val, true
diff --git a/toml_command_test.go b/toml_command_test.go
index 2f28d22..84558aa 100644
--- a/toml_command_test.go
+++ b/toml_command_test.go
@@ -7,20 +7,19 @@ package altsrc
 
 import (
 	"flag"
+	"github.com/urfave/cli/v2"
 	"io/ioutil"
 	"os"
 	"testing"
-
-	"gopkg.in/urfave/cli.v2"
 )
 
 func TestCommandTomFileTest(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
 	defer os.Remove("current.toml")
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -45,15 +44,15 @@ func TestCommandTomFileTest(t *testing.T) {
 }
 
 func TestCommandTomlFileTestGlobalEnvVarWins(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
 	defer os.Remove("current.toml")
 
-	os.Setenv("THE_TEST", "10")
+	_ = os.Setenv("THE_TEST", "10")
 	defer os.Setenv("THE_TEST", "")
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -79,15 +78,15 @@ func TestCommandTomlFileTestGlobalEnvVarWins(t *testing.T) {
 }
 
 func TestCommandTomlFileTestGlobalEnvVarWinsNested(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("[top]\ntest = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("[top]\ntest = 15"), 0666)
 	defer os.Remove("current.toml")
 
-	os.Setenv("THE_TEST", "10")
+	_ = os.Setenv("THE_TEST", "10")
 	defer os.Setenv("THE_TEST", "")
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -113,13 +112,13 @@ func TestCommandTomlFileTestGlobalEnvVarWinsNested(t *testing.T) {
 }
 
 func TestCommandTomlFileTestSpecifiedFlagWins(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
 	defer os.Remove("current.toml")
 
 	test := []string{"test-cmd", "--load", "current.toml", "--test", "7"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -145,14 +144,14 @@ func TestCommandTomlFileTestSpecifiedFlagWins(t *testing.T) {
 }
 
 func TestCommandTomlFileTestSpecifiedFlagWinsNested(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte(`[top]
+	_ = ioutil.WriteFile("current.toml", []byte(`[top]
   test = 15`), 0666)
 	defer os.Remove("current.toml")
 
 	test := []string{"test-cmd", "--load", "current.toml", "--top.test", "7"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -178,13 +177,13 @@ func TestCommandTomlFileTestSpecifiedFlagWinsNested(t *testing.T) {
 }
 
 func TestCommandTomlFileTestDefaultValueFileWins(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
 	defer os.Remove("current.toml")
 
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -210,13 +209,13 @@ func TestCommandTomlFileTestDefaultValueFileWins(t *testing.T) {
 }
 
 func TestCommandTomlFileTestDefaultValueFileWinsNested(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("[top]\ntest = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("[top]\ntest = 15"), 0666)
 	defer os.Remove("current.toml")
 
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -244,14 +243,14 @@ func TestCommandTomlFileTestDefaultValueFileWinsNested(t *testing.T) {
 func TestCommandTomlFileFlagHasDefaultGlobalEnvTomlSetGlobalEnvWins(t *testing.T) {
 	app := (&cli.App{})
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("test = 15"), 0666)
 	defer os.Remove("current.toml")
 
-	os.Setenv("THE_TEST", "11")
+	_ = os.Setenv("THE_TEST", "11")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -276,16 +275,16 @@ func TestCommandTomlFileFlagHasDefaultGlobalEnvTomlSetGlobalEnvWins(t *testing.T
 }
 
 func TestCommandTomlFileFlagHasDefaultGlobalEnvTomlSetGlobalEnvWinsNested(t *testing.T) {
-	app := (&cli.App{})
+	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.toml", []byte("[top]\ntest = 15"), 0666)
+	_ = ioutil.WriteFile("current.toml", []byte("[top]\ntest = 15"), 0666)
 	defer os.Remove("current.toml")
 
-	os.Setenv("THE_TEST", "11")
+	_ = os.Setenv("THE_TEST", "11")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", "current.toml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
diff --git a/toml_file_loader.go b/toml_file_loader.go
index 1cb2d7b..3f410fc 100644
--- a/toml_file_loader.go
+++ b/toml_file_loader.go
@@ -10,7 +10,7 @@ import (
 	"reflect"
 
 	"github.com/BurntSushi/toml"
-	"gopkg.in/urfave/cli.v2"
+	"github.com/urfave/cli/v2"
 )
 
 type tomlMap struct {
@@ -28,7 +28,7 @@ func unmarshalMap(i interface{}) (ret map[interface{}]interface{}, err error) {
 		case reflect.String:
 			ret[key] = val.(string)
 		case reflect.Int:
-			ret[key] = int(val.(int))
+			ret[key] = val.(int)
 		case reflect.Int8:
 			ret[key] = int(val.(int8))
 		case reflect.Int16:
@@ -50,7 +50,7 @@ func unmarshalMap(i interface{}) (ret map[interface{}]interface{}, err error) {
 		case reflect.Float32:
 			ret[key] = float64(val.(float32))
 		case reflect.Float64:
-			ret[key] = float64(val.(float64))
+			ret[key] = val.(float64)
 		case reflect.Map:
 			if tmp, err := unmarshalMap(val); err == nil {
 				ret[key] = tmp
@@ -66,9 +66,9 @@ func unmarshalMap(i interface{}) (ret map[interface{}]interface{}, err error) {
 	return ret, nil
 }
 
-func (self *tomlMap) UnmarshalTOML(i interface{}) error {
+func (tm *tomlMap) UnmarshalTOML(i interface{}) error {
 	if tmp, err := unmarshalMap(i); err == nil {
-		self.Map = tmp
+		tm.Map = tmp
 	} else {
 		return err
 	}
diff --git a/yaml_command_test.go b/yaml_command_test.go
index 5290e84..2190c2b 100644
--- a/yaml_command_test.go
+++ b/yaml_command_test.go
@@ -10,17 +10,16 @@ import (
 	"io/ioutil"
 	"os"
 	"testing"
-
-	"gopkg.in/urfave/cli.v2"
+	"github.com/urfave/cli/v2"
 )
 
 func TestCommandYamlFileTest(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
+	_ = ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
 	defer os.Remove("current.yaml")
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -47,13 +46,13 @@ func TestCommandYamlFileTest(t *testing.T) {
 func TestCommandYamlFileTestGlobalEnvVarWins(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
+	_ = ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
 	defer os.Remove("current.yaml")
 
-	os.Setenv("THE_TEST", "10")
+	_ = os.Setenv("THE_TEST", "10")
 	defer os.Setenv("THE_TEST", "")
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -81,14 +80,14 @@ func TestCommandYamlFileTestGlobalEnvVarWins(t *testing.T) {
 func TestCommandYamlFileTestGlobalEnvVarWinsNested(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte(`top:
+	_ = ioutil.WriteFile("current.yaml", []byte(`top:
   test: 15`), 0666)
 	defer os.Remove("current.yaml")
 
-	os.Setenv("THE_TEST", "10")
+	_ = os.Setenv("THE_TEST", "10")
 	defer os.Setenv("THE_TEST", "")
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -116,11 +115,11 @@ func TestCommandYamlFileTestGlobalEnvVarWinsNested(t *testing.T) {
 func TestCommandYamlFileTestSpecifiedFlagWins(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
+	_ = ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
 	defer os.Remove("current.yaml")
 
 	test := []string{"test-cmd", "--load", "current.yaml", "--test", "7"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -148,12 +147,12 @@ func TestCommandYamlFileTestSpecifiedFlagWins(t *testing.T) {
 func TestCommandYamlFileTestSpecifiedFlagWinsNested(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte(`top:
+	_ = ioutil.WriteFile("current.yaml", []byte(`top:
   test: 15`), 0666)
 	defer os.Remove("current.yaml")
 
 	test := []string{"test-cmd", "--load", "current.yaml", "--top.test", "7"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -181,11 +180,11 @@ func TestCommandYamlFileTestSpecifiedFlagWinsNested(t *testing.T) {
 func TestCommandYamlFileTestDefaultValueFileWins(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
+	_ = ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
 	defer os.Remove("current.yaml")
 
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -213,12 +212,12 @@ func TestCommandYamlFileTestDefaultValueFileWins(t *testing.T) {
 func TestCommandYamlFileTestDefaultValueFileWinsNested(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte(`top:
+	_ = ioutil.WriteFile("current.yaml", []byte(`top:
   test: 15`), 0666)
 	defer os.Remove("current.yaml")
 
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -246,14 +245,14 @@ func TestCommandYamlFileTestDefaultValueFileWinsNested(t *testing.T) {
 func TestCommandYamlFileFlagHasDefaultGlobalEnvYamlSetGlobalEnvWins(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
+	_ = ioutil.WriteFile("current.yaml", []byte("test: 15"), 0666)
 	defer os.Remove("current.yaml")
 
-	os.Setenv("THE_TEST", "11")
+	_ = os.Setenv("THE_TEST", "11")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
@@ -280,15 +279,15 @@ func TestCommandYamlFileFlagHasDefaultGlobalEnvYamlSetGlobalEnvWins(t *testing.T
 func TestCommandYamlFileFlagHasDefaultGlobalEnvYamlSetGlobalEnvWinsNested(t *testing.T) {
 	app := &cli.App{}
 	set := flag.NewFlagSet("test", 0)
-	ioutil.WriteFile("current.yaml", []byte(`top:
+	_ = ioutil.WriteFile("current.yaml", []byte(`top:
   test: 15`), 0666)
 	defer os.Remove("current.yaml")
 
-	os.Setenv("THE_TEST", "11")
+	_ = os.Setenv("THE_TEST", "11")
 	defer os.Setenv("THE_TEST", "")
 
 	test := []string{"test-cmd", "--load", "current.yaml"}
-	set.Parse(test)
+	_ = set.Parse(test)
 
 	c := cli.NewContext(app, set, nil)
 
diff --git a/yaml_file_loader.go b/yaml_file_loader.go
index 37c8d9c..9b1dc05 100644
--- a/yaml_file_loader.go
+++ b/yaml_file_loader.go
@@ -14,7 +14,7 @@ import (
 	"runtime"
 	"strings"
 
-	"gopkg.in/urfave/cli.v2"
+	"github.com/urfave/cli/v2"
 
 	"gopkg.in/yaml.v2"
 )
@@ -86,7 +86,7 @@ func loadDataFrom(filePath string) ([]byte, error) {
 			return nil, fmt.Errorf("Cannot read from file: '%s' because it does not exist.", filePath)
 		}
 		return ioutil.ReadFile(filePath)
-	} else {
-		return nil, fmt.Errorf("unable to determine how to load from path %s", filePath)
 	}
+
+	return nil, fmt.Errorf("unable to determine how to load from path %s", filePath)
 }