Add Brainfuck test

1 files changed, 84 insertions, 0 deletions

diff --git a/chapter15/src/test/java/com/seaofnodes/simple/Chapter15Test.java b/chapter15/src/test/java/com/seaofnodes/simple/Chapter15Test.java
index ad3c6b3f..00ed6c6c 100644
--- a/chapter15/src/test/java/com/seaofnodes/simple/Chapter15Test.java
+++ b/chapter15/src/test/java/com/seaofnodes/simple/Chapter15Test.java
@@ -5,6 +5,8 @@ import com.seaofnodes.simple.node.StopNode;
 import org.junit.Test;
 import org.junit.Ignore;
 
+import java.nio.charset.StandardCharsets;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
 
@@ -265,4 +267,86 @@ return is[1];
         catch( NegativeArraySizeException e ) { assertEquals("-1",e.getMessage()); }
     }
 
+    @Test
+    public void testBrainfuck() {
+        var program = "++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.".getBytes(StandardCharsets.UTF_8);
+        var encoded = new StringBuilder("u8[] program = new u8[").append(program.length).append("];");
+        for (int i = 0; i < program.length; i++) {
+            int value = program[i] & 0xFF;
+            encoded.append("program[").append(i).append("] = ").append(value).append(";");
+        }
+
+        Parser parser = new Parser(
+                encoded + """
+int pc = 0;
+int d = 0;
+u8[] data = new u8[30000];
+int i=0;
+while(i < data#) {
+    data[i] = 0;
+    i = i + 1;
+}
+
+u8[] output = new u8[0];
+
+while (pc < program#) {
+    int command = program[pc];
+    if (command == 62) {
+        d = d + 1;
+    } else if (command == 60) {
+        d = d - 1;
+    } else if (command == 43) {
+        data[d] = data[d] + 1;
+    } else if (command == 45) {
+        data[d] = data[d] - 1;
+    } else if (command == 46) {
+        u8[] old = output;
+        output = new u8[output# + 1];
+        i = 0;
+        while (i < old#) {
+            output[i] = old[i];
+            i = i + 1;
+        }
+        output[i] = data[d];
+    } else if (command == 44) {
+        data[d] = 42;
+    } else if (command == 91) {
+        if (data[d] == 0) {
+            int d = 1;
+            while (d > 0) {
+                pc = pc + 1;
+                command = program[pc];
+                if (command == 91) d = d + 1;
+                if (command == 93) d = d - 1;
+            }
+        }
+    } else if (command == 93) {
+        if (data[d] != 0) {
+            int d = 1;
+            while (d > 0) {
+                pc = pc - 1;
+                command = program[pc];
+                if (command == 93) d = d + 1;
+                if (command == 91) d = d - 1;
+            }
+        }
+    }
+    pc = pc + 1;
+}
+int result = 0;
+i = 0;
+while (i < 8) {
+    result = (result << 8) | data[i];
+    i = i + 1;
+}
+return result;
+                """);
+        StopNode stop = parser.parse(false).iterate(false);
+        long expected = 0;
+        for (byte b : "Hello Wo".getBytes(StandardCharsets.UTF_8)) {
+            expected = (expected << 8) | b;
+        }
+        assertEquals(expected, Evaluator.evaluate(stop, 1000000));
+    }
+
 }