diff --git a/src/wren_compiler.c b/src/wren_compiler.c
index 92a7e5c9..9a41c980 100644
--- a/src/wren_compiler.c
+++ b/src/wren_compiler.c
@@ -752,14 +752,7 @@ static void nextToken(Parser* parser)
         return;
 
       case '-':
-        if (isDigit(peekChar(parser)))
-        {
-          readNumber(parser);
-        }
-        else
-        {
-          makeToken(parser, TOKEN_MINUS);
-        }
+        makeToken(parser, TOKEN_MINUS);
         return;
 
       case '|':
diff --git a/test/grammar.wren b/test/grammar.wren
index 36590f70..cca6ec4e 100644
--- a/test/grammar.wren
+++ b/test/grammar.wren
@@ -25,6 +25,12 @@ IO.print(false == 1 >= 2) // expect: true
 // Unary - has lower precedence than ..
 IO.print(-"abc".count) // expect: -3
 
+// 1 - 1 is not space-sensitive.
+IO.print(1 - 1) // expect: 0
+IO.print(1 -1)  // expect: 0
+IO.print(1- 1)  // expect: 0
+IO.print(1-1)   // expect: 0
+
 // TODO: %, associativity.
 
 // Using () for grouping.
diff --git a/test/number/abs.wren b/test/number/abs.wren
index 31c1e444..171b3ebb 100644
--- a/test/number/abs.wren
+++ b/test/number/abs.wren
@@ -1,6 +1,6 @@
-IO.print(123.abs)    // expect: 123
-IO.print(-123.abs)   // expect: 123
-IO.print(0.abs)      // expect: 0
-IO.print(-0.abs)     // expect: 0
-IO.print(-0.12.abs)  // expect: 0.12
-IO.print(12.34.abs)  // expect: 12.34
+IO.print(123.abs)      // expect: 123
+IO.print((-123).abs)   // expect: 123
+IO.print(0.abs)        // expect: 0
+IO.print((-0).abs)     // expect: 0
+IO.print((-0.12).abs)  // expect: 0.12
+IO.print(12.34.abs)    // expect: 12.34
diff --git a/test/number/ceil.wren b/test/number/ceil.wren
index 8e180f2a..fe510dbd 100644
--- a/test/number/ceil.wren
+++ b/test/number/ceil.wren
@@ -1,8 +1,8 @@
-IO.print(123.ceil)    // expect: 123
-IO.print(-123.ceil)   // expect: -123
-IO.print(0.ceil)      // expect: 0
-IO.print(-0.ceil)     // expect: -0
-IO.print(0.123.ceil)  // expect: 1
-IO.print(12.3.ceil)   // expect: 13
-IO.print(-0.123.ceil) // expect: -0
-IO.print(-12.3.ceil)  // expect: -12
+IO.print(123.ceil)      // expect: 123
+IO.print((-123).ceil)   // expect: -123
+IO.print(0.ceil)        // expect: 0
+IO.print((-0).ceil)     // expect: -0
+IO.print(0.123.ceil)    // expect: 1
+IO.print(12.3.ceil)     // expect: 13
+IO.print((-0.123).ceil) // expect: -0
+IO.print((-12.3).ceil)  // expect: -12
diff --git a/test/number/floor.wren b/test/number/floor.wren
index b519ace3..063f0361 100644
--- a/test/number/floor.wren
+++ b/test/number/floor.wren
@@ -1,8 +1,8 @@
-IO.print(123.floor)    // expect: 123
-IO.print(-123.floor)   // expect: -123
-IO.print(0.floor)      // expect: 0
-IO.print(-0.floor)     // expect: -0
-IO.print(0.123.floor)  // expect: 0
-IO.print(12.3.floor)   // expect: 12
-IO.print(-0.123.floor) // expect: -1
-IO.print(-12.3.floor)  // expect: -13
+IO.print(123.floor)      // expect: 123
+IO.print((-123).floor)   // expect: -123
+IO.print(0.floor)        // expect: 0
+IO.print((-0).floor)     // expect: -0
+IO.print(0.123.floor)    // expect: 0
+IO.print(12.3.floor)     // expect: 12
+IO.print((-0.123).floor) // expect: -1
+IO.print((-12.3).floor)  // expect: -13
diff --git a/test/number/sqrt.wren b/test/number/sqrt.wren
index a4c2a668..f14cf979 100644
--- a/test/number/sqrt.wren
+++ b/test/number/sqrt.wren
@@ -1,10 +1,10 @@
 IO.print(4.sqrt)        // expect: 2
 IO.print(1000000.sqrt)  // expect: 1000
 IO.print(1.sqrt)        // expect: 1
-IO.print(-0.sqrt)       // expect: -0
+IO.print((-0).sqrt)     // expect: -0
 IO.print(0.sqrt)        // expect: 0
 IO.print(2.sqrt)        // expect: 1.4142135623731
 
-IO.print(-4.sqrt.isNan) // expect: true
+IO.print((-4).sqrt.isNan) // expect: true
 
 // TODO: Tests for sin and cos.
diff --git a/test/number/to_string.wren b/test/number/to_string.wren
index b02ca7e2..4ba6f896 100644
--- a/test/number/to_string.wren
+++ b/test/number/to_string.wren
@@ -1,5 +1,5 @@
 IO.print(123.toString == "123") // expect: true
-IO.print(-123.toString == "-123") // expect: true
-IO.print(-0.toString == "-0") // expect: true
+IO.print((-123).toString == "-123") // expect: true
+IO.print((-0).toString == "-0") // expect: true
 IO.print(12.34.toString == "12.34") // expect: true
-IO.print(-0.0001.toString == "-0.0001") // expect: true
+IO.print((-0.0001).toString == "-0.0001") // expect: true