Add bug pattern for unchecked enum creation with valueOf

[ghokun]

Context

Enum.valueOf method usage may lead to runtime exceptions when the provided argument is not checked against all possible values of method owner.

Example:

class Test {
  enum A {
    ONE, TWO, THREE
  }
  
  enum B {
    ONE, TWO, THREE, FOUR
  }
  
  // Will throw a runtime exception if b is equal to FOUR.
  A convertUnsafe(B b) {
    return A.valueOf(b.name());
  }
}

Scope

Of course it is not able to capture all possible checks on b before supplying it into A.valueOf. Therefore scope will be limited to following checks.

// BUG: Raw string
A convertUnsafe(String raw) {
  return A.valueOf(raw);
}

// BUG: From invalid string constant
A convertUnsafe() {
  return A.valueOf("FOUR");
}

// BUG: Where B has values that A do not have
A convertUnsafe(B b) {
  return A.valueOf(b.name());
}

// BUG: Value from case is not present in A
A convertUnsafe(B b) {
  return switch(b) { case FOUR -> A.valueOf(b.name()); };
}

// NOT BUG: From valid string constant
A convertSafe() {
  return A.valueOf("ONE");
}

Above checks should also consider the polymorphic variant of valueOf:

public static <T extends Enum<T>> T valueOf(Class<T> enumClass, String name)

[github-actions]

Suggested commit message:

Add `EnumValueOfUsage` bug pattern for unchecked `valueOf` usage (#2031)

Introduce an Error Prone check that flags `Enum#valueOf` invocations
with unchecked names, including raw strings and values from enums that
define additional constants.

Handle both overloads and account for switch filters to avoid
unchecked values reaching `valueOf`.

[github-actions]

• Surviving mutants in this change: 3
• Killed mutants in this change: 7

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfSuperSet	3	7

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[github-actions]

• Surviving mutants in this change: 2
• Killed mutants in this change: 7

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfSuperSet	2	7

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[github-actions]

• Surviving mutants in this change: 2
• Killed mutants in this change: 7

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfSuperSet	2	7

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[github-actions]

• Surviving mutants in this change: 12
• Killed mutants in this change: 16

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfUsage	12	16

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[ghokun]

We need to traverse back to switch case statement somehow to capture possible values of b.name(). If they are filtered by the switch case this should not be a bug.

Question: Should we do a similar check for possible if-else statements? I think scope will be too large to capture everything.

[ghokun]

I think this is enough to check if it is just a passed String.

[github-actions]

• Surviving mutants in this change: 6
• Killed mutants in this change: 24

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfUsage	6	24

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[github-actions]

[javac] _{reported by reviewdog 🐶}
[TypeToString] TypeMirror#toString shouldn't be used as it is expensive and fragile.

[github-actions]

• Surviving mutants in this change: 12
• Killed mutants in this change: 33

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfUsage	12	33

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
84.1% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

• Surviving mutants in this change: 12
• Killed mutants in this change: 33

class	surviving	killed
🧟tech.picnic.errorprone.bugpatterns.EnumValueOfUsage	12	33

Mutation testing report by Pitest. Review any surviving mutants by inspecting the line comments under Files changed.

• Arcmutate licence valid until 2027-10-20 (yyyy/mm/dd) (non-commercial use only)
• Project uses Spring, but the Arcmutate Spring plugin is not present.
• TestNG is on the classpath but the pitest TestNG plugin is not installed.

[ghokun]

I will try to resolve mutation test reports when I have the time.