Fix expression conversion

src/main/java/ch/njol/skript/lang/SkriptParser.java

@@ -326,7 +326,6 @@ private static <T> Variable<T> parseVariable(String expr, Class<? extends T>[] r
 		}
 	}
 
-
 	@Nullable
 	@SuppressWarnings({"unchecked", "rawtypes"})
 	private <T> Expression<? extends T> parseSingleExpr(boolean allowUnparsedLiteral, @Nullable LogEntry error, Class<? extends T>... types) {
@@ -370,22 +369,12 @@ private <T> Expression<? extends T> parseSingleExpr(boolean allowUnparsedLiteral
 				if (parsedExpression != null) { // Expression/VariableString parsing success
 					for (Class<? extends T> type : types) {
 						// Check return type against everything that expression accepts
-						if (parsedExpression.canReturn(type)) {
-							log.printLog();
-							return (Expression<? extends T>) parsedExpression;
-						}
+						if (parsedExpression.canReturn(type))
+							return convertExpression(parsedExpression, log, type);
 					}
 
 					// No directly same type found
-					Class<T>[] objTypes = (Class<T>[]) types; // Java generics... ?
-					Expression<? extends T> convertedExpression = parsedExpression.getConvertedExpression(objTypes);
-					if (convertedExpression != null) {
-						log.printLog();
-						return convertedExpression;
-					}
-					// Print errors, if we couldn't get the correct type
-					log.printError(parsedExpression.toString(null, false) + " " + Language.get("is") + " " + notOfType(types), ErrorQuality.NOT_AN_EXPRESSION);
-					return null;
+					return convertExpression(parsedExpression, log, (Class<T>[]) types);
 				}
 				log.clear();
 			}
@@ -556,8 +545,7 @@ private Expression<?> parseSingleExpr(boolean allowUnparsedLiteral, @Nullable Lo
 								return null;
 							}
 
-							log.printLog();
-							return parsedExpression;
+							return convertExpression(parsedExpression, log, type);
 						}
 					}
 
@@ -566,16 +554,8 @@ private Expression<?> parseSingleExpr(boolean allowUnparsedLiteral, @Nullable Lo
 						return null;
 					}
 
-					// No directly same type found
-					Expression<?> convertedExpression = parsedExpression.getConvertedExpression((Class<Object>[]) types);
-					if (convertedExpression != null) {
-						log.printLog();
-						return convertedExpression;
-					}
-
-					// Print errors, if we couldn't get the correct type
-					log.printError(parsedExpression.toString(null, false) + " " + Language.get("is") + " " + notOfType(types), ErrorQuality.NOT_AN_EXPRESSION);
-					return null;
+					//noinspection unchecked
+					return convertExpression(parsedExpression, log, (Class<Object>[]) types);
 				}
 				log.clear();
 			}
@@ -619,6 +599,17 @@ private Expression<?> parseSingleExpr(boolean allowUnparsedLiteral, @Nullable Lo
 		}
 	}
 
+	@SafeVarargs
+	private static <T> Expression<? extends T> convertExpression(Expression<?> expression, ParseLogHandler log, Class<T>... types) {
+		Expression<? extends T> convertedExpression = expression.getConvertedExpression(types);
+		if (convertedExpression != null) {
+			log.printLog();
+			return convertedExpression;
+		}
+		log.printError(expression.toString(null, false) + " " + Language.get("is") + " " + notOfType(types), ErrorQuality.NOT_AN_EXPRESSION);
+		return null;
+	}
+
 	/**
 	 * Matches ',', 'and', 'or', etc. as well as surrounding whitespace.
 	 * <p>

src/test/skript/tests/regressions/7164-expressions sometimes dont convert

@@ -0,0 +1,13 @@
+test "expressions sometimes dont convert":
+	assert formatted ({_foo} + {_bar}) is not set with "formatting nothing shouldn't throw an error"
+
+	set {_foo} to "test"
+	assert formatted ({_foo} + {_bar}) is not set with "formatting string + none shouldn't throw an error"
+
+	set {_foo} to 1
+	set {_bar} to 2
+	assert formatted ({_foo} + {_bar}) is not set with "formatting number + number shouldn't throw an error"
+
+	set {_foo} to "foo"
+	set {_bar} to "bar"
+	assert formatted ({_foo} + {_bar}) is "foobar" with "formatting strings doesn't work"