Fix warning with type conversion from rune + int to string

Signed-off-by: Chris Cummer <chriscummer@me.com>

app/focus_tracker.go

@@ -1,6 +1,7 @@
 package app
 
 import (
+	"fmt"
 	"sort"
 
 	"github.com/olebedev/config"
@@ -115,6 +116,7 @@ func (tracker *FocusTracker) Refocus() {
 
 // AssignHotKeys assigns an alphabetic keyboard character to each focusable
 // widget so that the widget can be brought into focus by pressing that keyboard key
+// Valid numbers are between 1 and 9, inclusive
 func (tracker *FocusTracker) assignHotKeys() {
 	if !tracker.useNavShortcuts() {
 		return
@@ -122,30 +124,37 @@ func (tracker *FocusTracker) assignHotKeys() {
 
 	usedKeys := make(map[string]bool)
 	focusables := tracker.focusables()
-	i := 1
 
+	// First, block out the explicitly-defined characters so they can't be automatically
+	// assigned to other modules
 	for _, focusable := range focusables {
 		if focusable.FocusChar() != "" {
 			usedKeys[focusable.FocusChar()] = true
 		}
 	}
+
+	focusNum := 1
+
+	// Range over all the modules and assign focus characters to any that are focusable
+	// and don't have explicitly-defined focus characters
 	for _, focusable := range focusables {
 		if focusable.FocusChar() != "" {
 			continue
 		}
-		if _, foundKey := usedKeys[string('0'+i)]; foundKey {
-			for ; foundKey; _, foundKey = usedKeys[string('0'+i)] {
-				i++
+
+		if _, foundKey := usedKeys[fmt.Sprint(focusNum)]; foundKey {
+			for ; foundKey; _, foundKey = usedKeys[fmt.Sprint(focusNum)] {
+				focusNum++
 			}
 		}
 
-		// Don't have nav characters > "9"
-		if i >= 10 {
+		// Don't allow focus characters > "9"
+		if focusNum >= 10 {
 			break
 		}
 
-		focusable.SetFocusChar(string('0' + i))
-		i++
+		focusable.SetFocusChar(fmt.Sprint(focusNum))
+		focusNum++
 	}
 }
 

cfg/common_settings.go

@@ -124,12 +124,18 @@ func (common *Common) DefaultRowColor() string {
 	)
 }
 
+// FocusChar returns the keyboard number assigned to the widget used to give onscreen
+// focus to this widget, as a string. Focus characters can be a range between 1 and 9
 func (common *Common) FocusChar() string {
-	if common.focusChar <= -1 {
+	if common.focusChar <= 0 {
 		return ""
 	}
 
-	return string('0' + common.focusChar)
+	if common.focusChar > 9 {
+		return ""
+	}
+
+	return fmt.Sprint(common.focusChar)
 }
 
 func (common *Common) RowColor(idx int) string {

cfg/common_settings_test.go

@@ -47,29 +47,36 @@ func Test_DefaultRowColor(t *testing.T) {
 func Test_FocusChar(t *testing.T) {
 	tests := []struct {
 		name         string
-		expectedChar string
 		before       func(testCfg *Common)
+		expectedChar string
 	}{
 		{
-			name:         "with no focus char specified",
-			expectedChar: "",
+			name: "with negative focus char",
 			before: func(testCfg *Common) {
 				testCfg.focusChar = -1
 			},
+			expectedChar: "",
 		},
 		{
-			name:         "with explicit focus char specified",
-			expectedChar: "3",
+			name: "with positive focus char",
 			before: func(testCfg *Common) {
 				testCfg.focusChar = 3
 			},
+			expectedChar: "3",
 		},
 		{
-			name:         "with ridiculous focus char specified",
-			expectedChar: "Q",
+			name: "with zero focus char",
 			before: func(testCfg *Common) {
-				testCfg.focusChar = 33
+				testCfg.focusChar = 0
 			},
+			expectedChar: "",
+		},
+		{
+			name: "with large focus char",
+			before: func(testCfg *Common) {
+				testCfg.focusChar = 10
+			},
+			expectedChar: "",
 		},
 	}