java.lang.correctness.hardcoded-conditional.hardcoded-conditional

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LGPL Commons Clause
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This if statement will always have the same behavior and is therefore unnecessary.

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Defintion

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rules:
  - id: hardcoded-conditional
    patterns:
      - pattern-either:
          - pattern: if (true) { ... }
          - pattern: if (false) { ... }
          - pattern: if ($VAR = true) { ... }
          - pattern: if ($VAR = false) { ... }
          - pattern: if ($EXPR && false) { ... }
          - pattern: if (false && $EXPR) { ... }
          - pattern: if ($EXPR || true) { ... }
          - pattern: if (true || $EXPR) { ... }
    message: This if statement will always have the same behavior and is therefore
      unnecessary.
    languages:
      - java
    severity: ERROR
    metadata:
      category: correctness
      technology:
        - java
      license: Commons Clause License Condition v1.0[LGPL-2.1-only]

Examples

hardcoded-conditional.java

class Bar {
    void main(boolean arg) {
        boolean myBoolean;

        // ruleid:hardcoded-conditional
        if (myBoolean = true) {
            continue;
        }
        // note that with new constant propagation, myBoolean is assumed
        // to true below

        // ruleid:hardcoded-conditional
        if (true) {
            continue;
        }

        // ruleid:hardcoded-conditional
        if (true && false) {
            continue;
        }

        // the dataflow constant-propagation now kicks in! this is true!
        // ruleid:hardcoded-conditional
        if (myBoolean) {

        }
        // to prevent constant propagation to assumes
        // myBoolean is true below
        myBoolean = arg;

        // ok:hardcoded-conditional
        if (myBoolean == myBoolean) {
            continue;
        }

        // ok:hardcoded-conditional
        if (myBoolean != myBoolean) {
            continue;
        }

        // ok:hardcoded-conditional
        if (moveToChild(curs, index, false, false))
        {
            removeToken(curs);
        }

    }
}