Add check for misspelled library examples folder name

Author: per1234

Diff for: check/checkconfigurations/checkconfigurations.go

@@ -926,6 +926,21 @@ var configurations = []Type{
 		ErrorModes:      []checkmode.Type{checkmode.Default},
 		CheckFunction:   checkfunctions.LibraryFolderNameGTMaxLength,
 	},
+	{
+		ProjectType:     projecttype.Library,
+		Category:        "structure",
+		Subcategory:     "",
+		ID:              "",
+		Brief:           "incorrect examples folder name",
+		Description:     "",
+		MessageTemplate: "Potentially misspelled examples folder name found: {{.}}. See: https://arduino.github.io/arduino-cli/latest/library-specification/#library-examples",
+		DisableModes:    nil,
+		EnableModes:     []checkmode.Type{checkmode.All},
+		InfoModes:       nil,
+		WarningModes:    []checkmode.Type{checkmode.Permissive},
+		ErrorModes:      []checkmode.Type{checkmode.Default},
+		CheckFunction:   checkfunctions.MisspelledExamplesFolderName,
+	},
 	{
 		ProjectType:     projecttype.Library,
 		Category:        "structure",

Diff for: check/checkfunctions/library.go

@@ -981,6 +981,22 @@ func LibraryFolderNameGTMaxLength() (result checkresult.Type, output string) {
 	return checkresult.Pass, ""
 }
 
+// MisspelledExamplesFolderName checks for incorrectly spelled `examples` folder name.
+func MisspelledExamplesFolderName() (result checkresult.Type, output string) {
+	directoryListing, err := checkdata.ProjectPath().ReadDir()
+	if err != nil {
+		panic(err)
+	}
+	directoryListing.FilterDirs()
+
+	path, found := containsMisspelledPathBaseName(directoryListing, "examples", "(?i)^e((x)|(xs)|(s))((am)|(ma))p((le)|(el))s?$")
+	if found {
+		return checkresult.Fail, path.String()
+	}
+
+	return checkresult.Pass, ""
+}
+
 // MisspelledExtrasFolderName checks for incorrectly spelled `extras` folder name.
 func MisspelledExtrasFolderName() (result checkresult.Type, output string) {
 	directoryListing, err := checkdata.ProjectPath().ReadDir()

Diff for: check/checkfunctions/library_test.go

@@ -282,6 +282,16 @@ func TestLibraryFolderNameGTMaxLength(t *testing.T) {
 	checkLibraryCheckFunction(LibraryFolderNameGTMaxLength, testTables, t)
 }
 
+func TestMisspelledExamplesFolderName(t *testing.T) {
+	testTables := []libraryCheckFunctionTestTable{
+		{"Correctly spelled", "ExamplesFolder", checkresult.Pass, ""},
+		{"Misspelled", "MisspelledExamplesFolder", checkresult.Fail, ""},
+		{"No examples folder", "Recursive", checkresult.Pass, ""},
+	}
+
+	checkLibraryCheckFunction(MisspelledExamplesFolderName, testTables, t)
+}
+
 func TestMisspelledExtrasFolderName(t *testing.T) {
 	testTables := []libraryCheckFunctionTestTable{
 		{"Correctly spelled", "ExtrasFolder", checkresult.Pass, ""},

Diff for: check/checkfunctions/testdata/libraries/ExamplesFolder/examples/Example/Example.ino

@@ -0,0 +1,2 @@
+void setup() {}
+void loop() {}

Diff for: check/checkfunctions/testdata/libraries/ExamplesFolder/library.properties

@@ -0,0 +1,9 @@
+name=ExamplesFolder
+version=1.0.0
+author=Cristian Maglie <[email protected]>, Pippo Pluto <[email protected]>
+maintainer=Cristian Maglie <[email protected]>
+sentence=A library that makes coding a web server a breeze.
+paragraph=Supports HTTP1.1 and you can do GET and POST.
+category=Communication
+url=http://example.com/
+architectures=avr

Diff for: check/checkfunctions/testdata/libraries/ExamplesFolder/src/ExamplesFolder.h

@@ -0,0 +1,2 @@
+void setup() {}
+void loop() {}

Diff for: check/checkfunctions/testdata/libraries/MisspelledExamplesFolder/example/Example/Example.ino

@@ -0,0 +1,9 @@
+name=MisspelledExamplesFolder
+version=1.0.0
+author=Cristian Maglie <[email protected]>, Pippo Pluto <[email protected]>
+maintainer=Cristian Maglie <[email protected]>
+sentence=A library that makes coding a web server a breeze.
+paragraph=Supports HTTP1.1 and you can do GET and POST.
+category=Communication
+url=http://example.com/
+architectures=avr