Fixes wrong priority of mathematical operations (#55)

* fix: change priority of mathematical operations

* test: add uvl model for mathematically correct expressions

* refactor: atom to primaryExpression

Author: MiriamGaus

tests/parsing/expressions.uvl

@@ -0,0 +1,30 @@
+features
+    A
+        or
+            B {Price 2, Fun 12}
+            C {Price 7, Fun 6}
+constraints
+    B.Fun + C.Fun - B.Price == 16
+    B.Fun + (C.Fun - B.Price) == 16
+    B.Fun + C.Fun * B.Price == 24
+    B.Fun + (C.Fun * B.Price) == 24
+    B.Fun + C.Fun / B.Price == 15
+    B.Fun + (C.Fun / B.Price) == 15
+    B.Fun - C.Fun + B.Price == 8
+    B.Fun - (C.Fun + B.Price) == 4
+    B.Fun - C.Fun * B.Price == 0
+    B.Fun - (C.Fun * B.Price) == 0
+    B.Fun - C.Fun / B.Price == 9
+    B.Fun - (C.Fun / B.Price) == 9
+    B.Fun * C.Fun / B.Price == 36
+    B.Fun * (C.Fun / B.Price) == 36
+    B.Fun * C.Fun - B.Price == 70
+    B.Fun * (C.Fun - B.Price) == 48
+    B.Fun * C.Fun + B.Price == 74
+    B.Fun * (C.Fun + B.Price) == 96
+    B.Fun / C.Fun * B.Price == 4
+    B.Fun / (C.Fun * B.Price) == 1
+    B.Fun / C.Fun + B.Price == 4
+    B.Fun / (C.Fun + B.Price) == 1.5
+    B.Fun / C.Fun - B.Price == 0
+    B.Fun / (C.Fun - B.Price) == 3

uvl/UVLBase.g4

@@ -72,17 +72,29 @@ equation
     | expression NOT_EQUALS expression      # NotEqualsEquation
     ;
 
-expression:
-    FLOAT                                   # FloatLiteralExpression
-    | INTEGER                               # IntegerLiteralExpression
-    | STRING                                # StringLiteralExpression
-    | aggregateFunction                     # AggregateFunctionExpression
-    | reference                             # LiteralExpression
-    | OPEN_PAREN expression CLOSE_PAREN     # BracketExpression
-    | expression ADD expression             # AddExpression
-    | expression SUB expression             # SubExpression
-    | expression MUL expression             # MulExpression
-    | expression DIV expression             # DivExpression
+expression
+    : additiveExpression
+    ;
+
+additiveExpression
+    : additiveExpression ADD multiplicativeExpression   # AddExpression
+    | additiveExpression SUB multiplicativeExpression   # SubExpression
+    | multiplicativeExpression                          # MultiplicativeExpr
+    ;
+
+multiplicativeExpression
+    : multiplicativeExpression MUL primaryExpression                # MulExpression
+    | multiplicativeExpression DIV primaryExpression                # DivExpression
+    | primaryExpression                                             # PrimaryExpressionExpression   
+    ;
+
+primaryExpression
+    : FLOAT                                   # FloatLiteralExpression
+    | INTEGER                                 # IntegerLiteralExpression
+    | STRING                                  # StringLiteralExpression
+    | aggregateFunction                       # AggregateFunctionExpression
+    | reference                               # LiteralExpression
+    | OPEN_PAREN expression CLOSE_PAREN       # BracketExpression
     ;
 
 aggregateFunction
@@ -160,4 +172,4 @@ SKIP_
 
   fragment SPACES
    : [ \t]+
-   ;
+   ;