From 64312cd1726c84d1082cc096db3923a6c55dd569 Mon Sep 17 00:00:00 2001
From: Arne Keller <arne.keller@student.kit.edu>
Date: Mon, 1 Feb 2021 11:08:31 +0100
Subject: [PATCH] More parser error handling tests

---
 .../typicalc/model/parser/LambdaLexer.java    |  9 -----
 .../typicalc/model/parser/LambdaParser.java   |  5 +--
 .../model/parser/LambdaParserTest.java        | 40 ++++++++++++++++++-
 3 files changed, 40 insertions(+), 14 deletions(-)

diff --git a/src/main/java/edu/kit/typicalc/model/parser/LambdaLexer.java b/src/main/java/edu/kit/typicalc/model/parser/LambdaLexer.java
index 95eea30..6f52d49 100644
--- a/src/main/java/edu/kit/typicalc/model/parser/LambdaLexer.java
+++ b/src/main/java/edu/kit/typicalc/model/parser/LambdaLexer.java
@@ -4,9 +4,7 @@ import edu.kit.typicalc.model.parser.Token.TokenType;
 import edu.kit.typicalc.util.Result;
 
 import java.util.ArrayDeque;
-import java.util.ArrayList;
 import java.util.Deque;
-import java.util.List;
 
 /**
  * This class lexes a term given as String into tokens.
@@ -71,13 +69,6 @@ public class LambdaLexer {
 
     }
 
-    public Result<List<Token>, ParseError> allTokens() {
-        if (result.isError()) {
-            return new Result<>(result);
-        }
-        return new Result<>(new ArrayList<>(result.unwrap()));
-    }
-
     private Result<Token, ParseError> parseNextToken() {
         while (pos < term.length() && Character.isWhitespace(term.charAt(pos))) {
             advance();
diff --git a/src/main/java/edu/kit/typicalc/model/parser/LambdaParser.java b/src/main/java/edu/kit/typicalc/model/parser/LambdaParser.java
index 67a06fd..2aab56f 100644
--- a/src/main/java/edu/kit/typicalc/model/parser/LambdaParser.java
+++ b/src/main/java/edu/kit/typicalc/model/parser/LambdaParser.java
@@ -186,10 +186,7 @@ public class LambdaParser {
         switch (token.getType()) {
             case VARIABLE:
                 Result<VarTerm, ParseError> var = parseVar();
-                if (var.isError()) {
-                    return new Result<>(var);
-                }
-                return new Result<>(var.unwrap());
+                return new Result<>(var.unwrap()); // variable token can always be parsed
             case NUMBER:
                 String number = token.getText();
                 int n;
diff --git a/src/test/java/edu/kit/typicalc/model/parser/LambdaParserTest.java b/src/test/java/edu/kit/typicalc/model/parser/LambdaParserTest.java
index 1d6bf29..5760f22 100644
--- a/src/test/java/edu/kit/typicalc/model/parser/LambdaParserTest.java
+++ b/src/test/java/edu/kit/typicalc/model/parser/LambdaParserTest.java
@@ -11,6 +11,7 @@ import edu.kit.typicalc.model.term.LetTerm;
 import edu.kit.typicalc.model.term.VarTerm;
 import edu.kit.typicalc.model.parser.Token.TokenType;
 import edu.kit.typicalc.util.Result;
+import nl.jqno.equalsverifier.EqualsVerifier;
 import org.junit.jupiter.api.Test;
 
 class LambdaParserTest {
@@ -82,7 +83,7 @@ class LambdaParserTest {
         );
     }
     @Test
-    void miscellaneousTerms() {
+    void errorHandling() {
         LambdaParser parser = new LambdaParser("");
         assertEquals(ParseError.TOO_FEW_TOKENS, parser.parse().unwrapError());
         parser = new LambdaParser("x)");
@@ -97,5 +98,42 @@ class LambdaParserTest {
         error = parser.parse().unwrapError();
         assertEquals(ParseError.UNEXPECTED_CHARACTER, error);
         assertEquals(new Token(TokenType.NUMBER, "123333333333333", 2), error.getCause());
+        parser = new LambdaParser("λ)");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.RIGHT_PARENTHESIS, ")", 1), error.getCause());
+        parser = new LambdaParser("λx=");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.EQUALS, "=", 2), error.getCause());
+        parser = new LambdaParser("λx..");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.DOT, ".", 3), error.getCause());
+        parser = new LambdaParser("let ) =");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.RIGHT_PARENTHESIS, ")", 4), error.getCause());
+        parser = new LambdaParser("let x .");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.DOT, ".", 6), error.getCause());
+        parser = new LambdaParser("let x = )");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.RIGHT_PARENTHESIS, ")", 8), error.getCause());
+        parser = new LambdaParser("let x = y )");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.RIGHT_PARENTHESIS, ")", 10), error.getCause());
+        parser = new LambdaParser("let x = y in )");
+        error = parser.parse().unwrapError();
+        assertEquals(ParseError.UNEXPECTED_TOKEN, error);
+        assertEquals(new Token(TokenType.RIGHT_PARENTHESIS, ")", 13), error.getCause());
+    }
+
+    @Test
+    void equality() {
+        EqualsVerifier.forClass(Token.class).usingGetClass().verify();
     }
 }