fix EmptyLinesWithinMethodsRule for function modules (SAP#106)

Author: jmgrassau

com.sap.adt.abapcleaner/src/com/sap/adt/abapcleaner/rules/emptylines/EmptyLinesWithinMethodsRule.java

@@ -22,6 +22,9 @@ public class EmptyLinesWithinMethodsRule extends Rule {
 	@Override
 	public String getDescription() { return "Restricts the number of consecutive empty lines within methods, and adds an empty line between declarations and the first executable statement (or the comments preceding it)."; }
 
+	@Override
+	public String getHintsAndRestrictions() { return "For function modules, additional empty lines are kept at the beginning to align with ADT and SE37 behavior."; }
+
 	@Override
 	public LocalDate getDateCreated() { return LocalDate.of(2020, 12, 28); }
 
@@ -136,6 +139,15 @@ private void executeOn(Code code, Command command, boolean insertLineBreakAbove)
 		Token token = command.getFirstToken();
 		if (command.getPrev() != null && (command.getPrev().isMethodFunctionFormOrEventBlockStart() || command.isMethodFunctionOrFormEnd())) {
 			int maxLineBreak = ((command.isMethodFunctionOrFormEnd()) ? configMaxEmptyLinesAtMethodEnd.getValue() : configMaxEmptyLinesAtMethodStart.getValue()) + 1;
+			
+			// for function modules with parameters, allow 3 extra lines that are needed for additional auto-generated comment lines in SE37, 
+			// and therefore ensured when saving a function module from ADT; for function modules without parameters, 1 extra line is needed
+			if (command.getPrev().isFunctionStart()) {
+				Token functionName = command.getPrev().getFirstCodeToken().getNextCodeSibling();
+				boolean hasParameters = (functionName != null && !functionName.getNextCodeSibling().isPeriod());
+				maxLineBreak += hasParameters ? 3 : 1;
+			}
+
 			if (token != null && token.lineBreaks > maxLineBreak) {
 				token.lineBreaks = maxLineBreak;
 				code.addRuleUse(this, command, token);

test/com.sap.adt.abapcleaner.test/src/com/sap/adt/abapcleaner/rules/emptylines/EmptyLinesWithinMethodsTest.java

@@ -351,4 +351,100 @@ void testIncludeType() {
 
 		testRule();
 	}
+
+	@Test
+	void testFunctionModuleWithParametersRemoveLine() {
+		// ensure that 3 empty lines are kept (but the 4th is removed) in function modules with parameters, 
+		// because these 3 lines are used for auto-generated comments in SE37 and reserved by ADT upon save 
+		
+		buildSrc("FUNCTION any_function");
+		buildSrc("  IMPORTING");
+		buildSrc("    VALUE(im_p1) TYPE i");
+		buildSrc("  EXPORTING");
+		buildSrc("    ex_p1 TYPE i.");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("  ex_p1 = 1.");
+		buildSrc("ENDFUNCTION.");
+
+		buildExp("FUNCTION any_function");
+		buildExp("  IMPORTING");
+		buildExp("    VALUE(im_p1) TYPE i");
+		buildExp("  EXPORTING");
+		buildExp("    ex_p1 TYPE i.");
+		buildExp("");
+		buildExp("");
+		buildExp("");
+		buildExp("  ex_p1 = 1.");
+		buildExp("ENDFUNCTION.");
+
+		testRule();
+	}
+
+	@Test
+	void testFunctionModuleWithParametersKeepLines() {
+		// with 1 empty line configured for method start, ensure that 4 empty lines are kept in function modules with parameters
+		
+		rule.configMaxEmptyLinesAtMethodStart.setValue(1);
+
+		buildSrc("FUNCTION any_function");
+		buildSrc("  IMPORTING");
+		buildSrc("    VALUE(im_p1) TYPE i");
+		buildSrc("  EXPORTING");
+		buildSrc("    ex_p1 TYPE i.");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("  ex_p1 = 1.");
+		buildSrc("ENDFUNCTION.");
+
+		copyExpFromSrc();
+
+		testRule();
+	}
+
+	@Test
+	void testFunctionModuleWithoutParametersRemoveLine() {
+		// ensure that 1 empty line is kept (but further lines removed) in function modules without parameters, 
+		// because this line is used for auto-generated comments in SE37 and reserved by ADT upon save 
+		
+		buildSrc("FUNCTION any_function");
+		buildSrc(" \" You can use the template 'functionModuleParameter' to add here the signature!");
+		buildSrc(".");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("  \" any comment");
+		buildSrc("ENDFUNCTION.");
+
+		buildExp("FUNCTION any_function");
+		buildExp(" \" You can use the template 'functionModuleParameter' to add here the signature!");
+		buildExp(".");
+		buildExp("");
+		buildExp("  \" any comment");
+		buildExp("ENDFUNCTION.");
+
+		testRule();
+	}
+
+	@Test
+	void testFunctionModuleWithoutParametersKeepLines() {
+		// with 1 empty line configured for method start, ensure that 2 empty lines are kept in function modules without parameters
+
+		rule.configMaxEmptyLinesAtMethodStart.setValue(1);
+
+		buildSrc("FUNCTION any_function");
+		buildSrc(" \" You can use the template 'functionModuleParameter' to add here the signature!");
+		buildSrc(".");
+		buildSrc("");
+		buildSrc("");
+		buildSrc("  \" any comment");
+		buildSrc("ENDFUNCTION.");
+
+		copyExpFromSrc();
+
+		testRule();
+	}
 }