Convert some deob-ast methods to extension methods

deob-ast/src/main/java/dev/openrs2/deob/ast/transform/AddSubTransformer.kt

@@ -21,11 +21,11 @@ class AddSubTransformer : Transformer() {
                 return@walk
             }
 
-            if (op == BinaryExpr.Operator.PLUS && isNegative(right)) {
+            if (op == BinaryExpr.Operator.PLUS && right.isNegative()) {
                 // x + -y => x - y
                 expr.operator = BinaryExpr.Operator.MINUS
                 expr.right = right.negate()
-            } else if (op == BinaryExpr.Operator.PLUS && isNegative(left)) {
+            } else if (op == BinaryExpr.Operator.PLUS && left.isNegative()) {
                 if (expr.hasSideEffects()) {
                     return@walk
                 }
@@ -34,7 +34,7 @@ class AddSubTransformer : Transformer() {
                 expr.operator = BinaryExpr.Operator.MINUS
                 expr.left = right.clone()
                 expr.right = left.negate()
-            } else if (op == BinaryExpr.Operator.MINUS && isNegative(right)) {
+            } else if (op == BinaryExpr.Operator.MINUS && right.isNegative()) {
                 // x - -y => x + y
                 expr.operator = BinaryExpr.Operator.PLUS
                 expr.right = right.negate()
@@ -42,14 +42,12 @@ class AddSubTransformer : Transformer() {
         }
     }
 
-    companion object {
-        private fun isNegative(expr: Expression): Boolean {
+    private fun Expression.isNegative(): Boolean {
         return when {
-                expr.isUnaryExpr -> expr.asUnaryExpr().operator == UnaryExpr.Operator.MINUS
-                expr.isIntegerLiteralExpr -> expr.asIntegerLiteralExpr().asInt() < 0
-                expr.isLongLiteralExpr -> expr.asLongLiteralExpr().asLong() < 0
+            isUnaryExpr -> asUnaryExpr().operator == UnaryExpr.Operator.MINUS
+            isIntegerLiteralExpr -> asIntegerLiteralExpr().asInt() < 0
+            isLongLiteralExpr -> asLongLiteralExpr().asLong() < 0
             else -> false
         }
     }
-    }
 }

deob-ast/src/main/java/dev/openrs2/deob/ast/transform/BinaryExprOrderTransformer.kt

@@ -8,7 +8,7 @@ import dev.openrs2.deob.ast.util.walk
 class BinaryExprOrderTransformer : Transformer() {
     override fun transform(unit: CompilationUnit) {
         unit.walk { expr: BinaryExpr ->
-            val op = flip(expr.operator) ?: return@walk
+            val op = expr.operator.flip() ?: return@walk
 
             val type = expr.calculateResolvedType()
             if (op == BinaryExpr.Operator.PLUS && type.isString()) {
@@ -25,13 +25,12 @@ class BinaryExprOrderTransformer : Transformer() {
         }
     }
 
-    companion object {
-        private fun flip(op: BinaryExpr.Operator): BinaryExpr.Operator? {
-            return when (op) {
-                BinaryExpr.Operator.PLUS, BinaryExpr.Operator.MULTIPLY -> op
-                BinaryExpr.Operator.EQUALS, BinaryExpr.Operator.NOT_EQUALS -> op
-                BinaryExpr.Operator.BINARY_AND, BinaryExpr.Operator.BINARY_OR -> op
-                BinaryExpr.Operator.XOR, BinaryExpr.Operator.OR, BinaryExpr.Operator.AND -> op
+    private fun BinaryExpr.Operator.flip(): BinaryExpr.Operator? {
+        return when (this) {
+            BinaryExpr.Operator.PLUS, BinaryExpr.Operator.MULTIPLY -> this
+            BinaryExpr.Operator.EQUALS, BinaryExpr.Operator.NOT_EQUALS -> this
+            BinaryExpr.Operator.BINARY_AND, BinaryExpr.Operator.BINARY_OR -> this
+            BinaryExpr.Operator.XOR, BinaryExpr.Operator.OR, BinaryExpr.Operator.AND -> this
             BinaryExpr.Operator.GREATER -> BinaryExpr.Operator.LESS
             BinaryExpr.Operator.GREATER_EQUALS -> BinaryExpr.Operator.LESS_EQUALS
             BinaryExpr.Operator.LESS -> BinaryExpr.Operator.GREATER
@@ -39,5 +38,4 @@ class BinaryExprOrderTransformer : Transformer() {
             else -> null
         }
     }
-    }
 }

deob-ast/src/main/java/dev/openrs2/deob/ast/transform/ComplementTransformer.kt

@@ -18,21 +18,21 @@ class ComplementTransformer : Transformer() {
             val right = expr.right
             val bothLiteral = left.isIntegerOrLongLiteral() && right.isIntegerOrLongLiteral()
 
-            if (isComplementOrLiteral(left) && isComplementOrLiteral(right) && !bothLiteral) {
+            if (left.isComplementOrLiteral() && right.isComplementOrLiteral() && !bothLiteral) {
                 expr.operator = op
-                expr.left = complement(left)
-                expr.right = complement(right)
+                expr.left = left.complement()
+                expr.right = right.complement()
             }
         }
     }
 
     companion object {
-        private fun isComplement(expr: Expression): Boolean {
-            return expr.isUnaryExpr && expr.asUnaryExpr().operator == UnaryExpr.Operator.BITWISE_COMPLEMENT
+        private fun Expression.isComplement(): Boolean {
+            return isUnaryExpr && asUnaryExpr().operator == UnaryExpr.Operator.BITWISE_COMPLEMENT
         }
 
-        private fun isComplementOrLiteral(expr: Expression): Boolean {
-            return isComplement(expr) || expr.isIntegerOrLongLiteral()
+        private fun Expression.isComplementOrLiteral(): Boolean {
+            return isComplement() || isIntegerOrLongLiteral()
         }
 
         private fun complement(op: BinaryExpr.Operator): BinaryExpr.Operator? {
@@ -46,11 +46,11 @@ class ComplementTransformer : Transformer() {
             }
         }
 
-        private fun complement(expr: Expression): Expression {
+        private fun Expression.complement(): Expression {
             return when {
-                expr.isUnaryExpr -> expr.asUnaryExpr().expression
-                expr.isIntegerLiteralExpr -> IntegerLiteralExpr(expr.asIntegerLiteralExpr().asInt().inv())
-                expr.isLongLiteralExpr -> createLong(expr.asLongLiteralExpr().asLong().inv())
+                isUnaryExpr -> asUnaryExpr().expression
+                isIntegerLiteralExpr -> IntegerLiteralExpr(asIntegerLiteralExpr().asInt().inv())
+                isLongLiteralExpr -> createLong(asLongLiteralExpr().asLong().inv())
                 else -> throw IllegalArgumentException()
             }
         }

deob-ast/src/main/java/dev/openrs2/deob/ast/transform/IdentityTransformer.kt

@@ -12,28 +12,28 @@ class IdentityTransformer : Transformer() {
             @Suppress("NON_EXHAUSTIVE_WHEN")
             when (expr.operator) {
                 BinaryExpr.Operator.PLUS -> {
-                    if (isZero(expr.left)) {
+                    if (expr.left.isZero()) {
                         // 0 + x => x
                         expr.replace(expr.right)
-                    } else if (isZero(expr.right)) {
+                    } else if (expr.right.isZero()) {
                         // x + 0 => x
                         expr.replace(expr.left)
                     }
                 }
                 BinaryExpr.Operator.MINUS -> {
-                    if (isZero(expr.left)) {
+                    if (expr.left.isZero()) {
                         // 0 - x => -x
                         expr.replace(UnaryExpr(expr.right, UnaryExpr.Operator.MINUS))
-                    } else if (isZero(expr.right)) {
+                    } else if (expr.right.isZero()) {
                         // x - 0 => x
                         expr.replace(expr.left)
                     }
                 }
                 BinaryExpr.Operator.MULTIPLY -> {
-                    if (isOne(expr.left)) {
+                    if (expr.left.isOne()) {
                         // 1 * x => x
                         expr.replace(expr.right)
-                    } else if (isOne(expr.right)) {
+                    } else if (expr.right.isOne()) {
                         // x * 1 => x
                         expr.replace(expr.left)
                     }
@@ -42,21 +42,19 @@ class IdentityTransformer : Transformer() {
         }
     }
 
-    companion object {
-        private fun isZero(expr: Expression): Boolean {
+    private fun Expression.isZero(): Boolean {
         return when {
-                expr.isIntegerLiteralExpr -> expr.asIntegerLiteralExpr().asNumber() == 0
-                expr.isLongLiteralExpr -> expr.asLongLiteralExpr().asNumber() == 0L
+            isIntegerLiteralExpr -> asIntegerLiteralExpr().asNumber() == 0
+            isLongLiteralExpr -> asLongLiteralExpr().asNumber() == 0L
             else -> false
         }
     }
 
-        private fun isOne(expr: Expression): Boolean {
+    private fun Expression.isOne(): Boolean {
         return when {
-                expr.isIntegerLiteralExpr -> expr.asIntegerLiteralExpr().asNumber() == 1
-                expr.isLongLiteralExpr -> expr.asLongLiteralExpr().asNumber() == 1L
+            isIntegerLiteralExpr -> asIntegerLiteralExpr().asNumber() == 1
+            isLongLiteralExpr -> asLongLiteralExpr().asNumber() == 1L
             else -> false
         }
     }
-    }
 }

deob-ast/src/main/java/dev/openrs2/deob/ast/transform/IfElseTransformer.kt

@@ -14,11 +14,11 @@ class IfElseTransformer : Transformer() {
             stmt.elseStmt.ifPresent { elseStmt: Statement ->
                 val condition = stmt.condition
                 val thenStmt = stmt.thenStmt
-                if (isIf(thenStmt) && !isIf(elseStmt)) {
+                if (thenStmt.isIf() && !elseStmt.isIf()) {
                     stmt.condition = condition.not()
                     stmt.thenStmt = elseStmt.clone()
                     stmt.setElseStmt(thenStmt.clone())
-                } else if (!isIf(thenStmt) && isIf(elseStmt)) {
+                } else if (!thenStmt.isIf() && elseStmt.isIf()) {
                     /*
                      * Don't consider any more conditions for swapping the
                      * if/else branches, as it'll introduce another level of
@@ -45,8 +45,8 @@ class IfElseTransformer : Transformer() {
 
         unit.walk { stmt: IfStmt ->
             stmt.elseStmt.ifPresent { elseStmt ->
-                if (isIf(elseStmt)) {
-                    stmt.setElseStmt(getIf(elseStmt))
+                if (elseStmt.isIf()) {
+                    stmt.setElseStmt(elseStmt.getIf())
                 }
             }
         }
@@ -97,7 +97,7 @@ class IfElseTransformer : Transformer() {
                 }
 
                 val thenStmt = ifStmt.thenStmt
-                if (!isTailThrowOrReturn(thenStmt)) {
+                if (!thenStmt.isTailThrowOrReturn()) {
                     return@ifPresent
                 }
 
@@ -112,23 +112,22 @@ class IfElseTransformer : Transformer() {
         }
     }
 
-    companion object {
-        private fun isIf(stmt: Statement): Boolean {
+    private fun Statement.isIf(): Boolean {
         return when {
-                stmt.isIfStmt -> true
-                stmt.isBlockStmt -> {
-                    val stmts = stmt.asBlockStmt().statements
+            isIfStmt -> true
+            isBlockStmt -> {
+                val stmts = asBlockStmt().statements
                 stmts.size == 1 && stmts[0].isIfStmt
             }
             else -> false
         }
     }
 
-        private fun getIf(stmt: Statement): Statement {
-            if (stmt.isIfStmt) {
-                return stmt.clone()
-            } else if (stmt.isBlockStmt) {
-                val stmts = stmt.asBlockStmt().statements
+    private fun Statement.getIf(): Statement {
+        if (isIfStmt) {
+            return clone()
+        } else if (isBlockStmt) {
+            val stmts = asBlockStmt().statements
             if (stmts.size == 1) {
                 val head = stmts[0]
                 if (head.isIfStmt) {
@@ -139,11 +138,11 @@ class IfElseTransformer : Transformer() {
         throw IllegalArgumentException()
     }
 
-        private fun isTailThrowOrReturn(stmt: Statement): Boolean {
-            return if (stmt.isThrowStmt || stmt.isReturnStmt) {
+    private fun Statement.isTailThrowOrReturn(): Boolean {
+        return if (isThrowStmt || isReturnStmt) {
             true
-            } else if (stmt.isBlockStmt) {
-                val stmts = stmt.asBlockStmt().statements
+        } else if (isBlockStmt) {
+            val stmts = asBlockStmt().statements
             if (stmts.isEmpty()) {
                 return false
             }
@@ -154,5 +153,4 @@ class IfElseTransformer : Transformer() {
             false
         }
     }
-    }
 }

deob-ast/src/main/java/dev/openrs2/deob/ast/transform/IncrementTransformer.kt

@@ -14,7 +14,7 @@ class IncrementTransformer : Transformer() {
             }
 
             val unaryExpr = stmt.expression.asUnaryExpr()
-            unaryExpr.operator = prefixToPostfix(unaryExpr.operator)
+            unaryExpr.operator = unaryExpr.operator.toPostfix()
         }
 
         unit.walk { stmt: ForStmt ->
@@ -24,16 +24,14 @@ class IncrementTransformer : Transformer() {
                 }
 
                 val unaryExpr = expr.asUnaryExpr()
-                unaryExpr.operator = prefixToPostfix(unaryExpr.operator)
+                unaryExpr.operator = unaryExpr.operator.toPostfix()
             }
         }
     }
 
-    companion object {
-        private fun prefixToPostfix(operator: UnaryExpr.Operator) = when (operator) {
+    private fun UnaryExpr.Operator.toPostfix() = when (this) {
         UnaryExpr.Operator.PREFIX_INCREMENT -> UnaryExpr.Operator.POSTFIX_INCREMENT
         UnaryExpr.Operator.PREFIX_DECREMENT -> UnaryExpr.Operator.POSTFIX_DECREMENT
-            else -> operator
-        }
+        else -> this
     }
 }