Add string formatting exercise

Author: kawpii

internal/exercises/catalog.yaml

@@ -159,6 +159,11 @@ concepts:
   test_regex: ".*"
   hints:
     - Use `slices.Sort` to sort slices.
+- slug: 33_string_formatting
+  title: String Formatting
+  test_regex: ".*"
+  hints:
+    - Format strings accordingly using `%s`, `%d`, and `%f`.
 
 projects:
 - slug: 101_text_analyzer

internal/exercises/solutions/33_string_formatting/string_formatting.go

@@ -0,0 +1,15 @@
+package string_formatting
+
+import "fmt"
+
+func FormatName() string {
+	return fmt.Sprintf("Name: %s", "\"John\"")
+}
+
+func FormatAge() string {
+	return fmt.Sprintf("Age: %d", 17)
+}
+
+func FormatGpa() string {
+	return fmt.Sprintf("GPA: %.2f", 3.75)
+}

internal/exercises/templates/33_string_formatting/string_formatting.go

@@ -0,0 +1,15 @@
+package string_formatting
+
+import "fmt"
+
+func FormatName() string {
+	return fmt.Sprintf("Name: ", "\"John\"")
+}
+
+func FormatAge() string {
+	return fmt.Sprintf("Age: ", 17)
+}
+
+func FormatGpa() string {
+	return fmt.Sprintf("GPA: ", 3.75)
+}

internal/exercises/templates/33_string_formatting/string_formatting_test.go

@@ -0,0 +1,34 @@
+package string_formatting
+
+import (
+	"testing"
+)
+
+func TestStringFormats(t *testing.T) {
+	t.Run("Name should be formatted as a string!", func(t *testing.T) {
+		got := FormatName()
+		want := "Name: \"John\""
+
+		if got != want {
+			t.Errorf("Expected %q, got %q", want, got)
+		}
+	})
+
+	t.Run("Age should formatted as a digit!", func(t *testing.T) {
+		got := FormatAge()
+		want := "Age: 17"
+
+		if got != want {
+			t.Errorf("Expected %q got %q", want, got)
+		}
+	})
+
+	t.Run("GPA should be formatted for floating point number with 2 decimal places!", func(t *testing.T) {
+		got := FormatGpa()
+		want := "GPA: 3.75"
+
+		if got != want {
+			t.Errorf("Expected %q got %q", want, got)
+		}
+	})
+}