Compilation error in KotlinGenerator generated code with KeepNamesGeneratorStrategy and generated implicit join paths

[lukaseder]

Discovered when writing tests for #15942, when using KeepNamesGeneratorStrategy with the KotlinGenerator and with implicit join paths, then there's a compilation error for a schema like this:

CREATE TABLE parent (
  id INT,
  CONSTRAINT pk_parent PRIMARY KEY (id)
);

CREATE TABLE "PascalCase" ("PascalCaseColumn" INT, CONSTRAINT fk_pascal_case FOREIGN KEY ("PascalCaseColumn") REFERENCES parent);
CREATE TABLE "camelCase" ("camelCaseColumn" INT, CONSTRAINT fk_camel_case FOREIGN KEY ("camelCaseColumn") REFERENCES parent);
CREATE TABLE "UPPER_CASE" ("UPPER_CASE_COLUMN" INT, CONSTRAINT fk_upper_case FOREIGN KEY ("UPPER_CASE_COLUMN") REFERENCES parent);
CREATE TABLE "lower_case" ("lower_case_column" INT, CONSTRAINT fk_lower_case FOREIGN KEY ("lower_case_column") REFERENCES parent);

Problematic code includes:

    override fun getReferences(): List<ForeignKey<org.jooq.codegen.test.keepnamesgeneratorstrategy.db.tables.records.lower_case, *>> = listOf(FK_LOWER_CASE)
    // Error here --------------------------------------------------------------------------------------------------------------------------- ^^^^^^^^^^^^^

    private lateinit var _FK_LOWER_CASE: PARENT_PATH

    /**
     * Get the implicit join path to the <code>PUBLIC.PARENT</code> table.
     */
    internal fun FK_LOWER_CASE(): PARENT_PATH {
        if (!this::_FK_LOWER_CASE.isInitialized)
            _FK_LOWER_CASE = PARENT_PATH(this, FK_LOWER_CASE, null) 
            // Error here -------------------- ^^^^^^^^^^^^^

        return _FK_LOWER_CASE;
    }

    internal val FK_LOWER_CASE: PARENT_PATH
        get(): PARENT_PATH = FK_LOWER_CASE()

And the compilation error is:

[ERROR] C:\Users\lukas\jOOQ\3.20\workspace\jOOQ-pro\jOOQ-test-codegen\jOOQ-test-codegen-kotlin\src\test\kotlin\org\jooq\codegen\test\keepnamesgeneratorstrategy\db\tables\lower_case.kt:[109,136] Type mismatch: inferred type is PARENT.PARENT_PATH but ForeignKey<lower_case, *> was expected
[ERROR] C:\Users\lukas\jOOQ\3.20\workspace\jOOQ-pro\jOOQ-test-codegen\jOOQ-test-codegen-kotlin\src\test\kotlin\org\jooq\codegen\test\keepnamesgeneratorstrategy\db\tables\lower_case.kt:[109,136] Type mismatch: inferred type is List<PARENT.PARENT_PATH> but List<ForeignKey<lower_case, *>> was expected
[ERROR] C:\Users\lukas\jOOQ\3.20\workspace\jOOQ-pro\jOOQ-test-codegen\jOOQ-test-codegen-kotlin\src\test\kotlin\org\jooq\codegen\test\keepnamesgeneratorstrategy\db\tables\lower_case.kt:[118,48] Type mismatch: inferred type is PARENT.PARENT_PATH but ForeignKey<out Record, PARENT>? was expected

[lukaseder]

The fix is implemented with #15942, but parts of the fix can also be backported to older releases

[lukaseder]

Fixed in versions:

• 3.20.0
• 3.19.1 (Compilation error in KotlinGenerator generated code with KeepNamesGeneratorStrategy and generated implicit join paths - Merge [#15946] #15948)
• 3.18.8 (Compilation error in KotlinGenerator generated code with KeepNamesGeneratorStrategy and generated implicit join paths - Merge [#15946] #15949)
• 3.17.17 (Compilation error in KotlinGenerator generated code with KeepNamesGeneratorStrategy and generated implicit join paths - Merge [#15946] #15950)
• 3.16.23 (Compilation error in KotlinGenerator generated code with KeepNamesGeneratorStrategy and generated implicit join paths - Merge [#15946] #15951)