Added the test-cases from canonical-data.json to exercise diamond (#2255

)

exercises/practice/diamond/.meta/gen.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"log"
+	"text/template"
+
+	"../../../../gen"
+)
+
+func main() {
+	t, err := template.New("").Parse(tmpl)
+	if err != nil {
+		log.Fatal(err)
+	}
+	var j js
+	if err := gen.Gen("diamond", &j, t); err != nil {
+		log.Fatal(err)
+	}
+}
+
+// The JSON structure we expect to be able to unmarshal into
+type js struct {
+	Cases []struct {
+		Description string `json:"description"`
+		Input       struct {
+			Letter string `json:"letter"`
+		} `json:"input"`
+		Expected []string `json:"expected"`
+	} `json:"cases"`
+}
+
+// template applied to above data structure generates the Go test cases
+var tmpl = `package diamond
+
+{{.Header}}
+
+var testCases = []struct {
+	description string
+	input       string
+	expected    []string
+	expectedError error
+}{
+{{range .J.Cases}}{
+		description: {{printf "%q"   .Description}},
+	input: {{printf "%q"   .Input.Letter}},
+	expectedError: nil,
+	expected: []string { {{range $line := .Expected}}{{printf "\n%q," $line}}{{end}}
+},
+},
+{{end}}
+}`

exercises/practice/diamond/.meta/tests.toml

@@ -1,6 +1,13 @@
-# This is an auto-generated file. Regular comments will be removed when this
-# file is regenerated. Regenerating will not touch any manually added keys,
-# so comments can be added in a "comment" key.
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
 
 [202fb4cc-6a38-4883-9193-a29d5cb92076]
 description = "Degenerate case with a single 'A' row"

exercises/practice/diamond/cases_test.go

@@ -0,0 +1,114 @@
+package diamond
+
+// Source: exercism/problem-specifications
+// Commit: d137db1 Format using prettier (#1917)
+
+var testCases = []struct {
+	description   string
+	input         string
+	expected      []string
+	expectedError error
+}{
+	{
+		description:   "Degenerate case with a single 'A' row",
+		input:         "A",
+		expectedError: nil,
+		expected: []string{
+			"A",
+		},
+	},
+	{
+		description:   "Degenerate case with no row containing 3 distinct groups of spaces",
+		input:         "B",
+		expectedError: nil,
+		expected: []string{
+			" A ",
+			"B B",
+			" A ",
+		},
+	},
+	{
+		description:   "Smallest non-degenerate case with odd diamond side length",
+		input:         "C",
+		expectedError: nil,
+		expected: []string{
+			"  A  ",
+			" B B ",
+			"C   C",
+			" B B ",
+			"  A  ",
+		},
+	},
+	{
+		description:   "Smallest non-degenerate case with even diamond side length",
+		input:         "D",
+		expectedError: nil,
+		expected: []string{
+			"   A   ",
+			"  B B  ",
+			" C   C ",
+			"D     D",
+			" C   C ",
+			"  B B  ",
+			"   A   ",
+		},
+	},
+	{
+		description:   "Largest possible diamond",
+		input:         "Z",
+		expectedError: nil,
+		expected: []string{
+			"                         A                         ",
+			"                        B B                        ",
+			"                       C   C                       ",
+			"                      D     D                      ",
+			"                     E       E                     ",
+			"                    F         F                    ",
+			"                   G           G                   ",
+			"                  H             H                  ",
+			"                 I               I                 ",
+			"                J                 J                ",
+			"               K                   K               ",
+			"              L                     L              ",
+			"             M                       M             ",
+			"            N                         N            ",
+			"           O                           O           ",
+			"          P                             P          ",
+			"         Q                               Q         ",
+			"        R                                 R        ",
+			"       S                                   S       ",
+			"      T                                     T      ",
+			"     U                                       U     ",
+			"    V                                         V    ",
+			"   W                                           W   ",
+			"  X                                             X  ",
+			" Y                                               Y ",
+			"Z                                                 Z",
+			" Y                                               Y ",
+			"  X                                             X  ",
+			"   W                                           W   ",
+			"    V                                         V    ",
+			"     U                                       U     ",
+			"      T                                     T      ",
+			"       S                                   S       ",
+			"        R                                 R        ",
+			"         Q                               Q         ",
+			"          P                             P          ",
+			"           O                           O           ",
+			"            N                         N            ",
+			"             M                       M             ",
+			"              L                     L              ",
+			"               K                   K               ",
+			"                J                 J                ",
+			"                 I               I                 ",
+			"                  H             H                  ",
+			"                   G           G                   ",
+			"                    F         F                    ",
+			"                     E       E                     ",
+			"                      D     D                      ",
+			"                       C   C                       ",
+			"                        B B                        ",
+			"                         A                         ",
+		},
+	},
+}

exercises/practice/diamond/diamond_test.go

@@ -1,6 +1,7 @@
 package diamond
 
 import (
+	"fmt"
 	"math/rand"
 	"reflect"
 	"strings"
@@ -38,6 +39,22 @@ func checkCorrect(requirement func(byte, []string) bool, keepSeparator bool, t *
 	}
 }
 
+func TestDiamond(t *testing.T) {
+	for _, testCase := range testCases {
+		t.Run(testCase.description, func(t *testing.T) {
+			expected := fmt.Sprintf("%s\n", strings.Join(testCase.expected, "\n"))
+			got, err := Gen(testCase.input[0])
+
+			if err != testCase.expectedError {
+				t.Fatalf("Gen(%q)\nExpected:%v\nGot:%v", testCase.input, testCase.expectedError, err)
+			}
+			if got != expected {
+				t.Fatalf("Gen(%q)\nExpected:\n%s\n(len=%d)\nGot:\n%s\n(len=%d)", testCase.input, expected, len(expected), got, len(got))
+			}
+		})
+	}
+}
+
 func TestFirstRowContainsOneA(t *testing.T) {
 	requirement := func(char byte, rows []string) bool {
 		return len(rows) > 0 && strings.Count(rows[0], "A") == 1