[fine] Tests for type errors

WHEEEEEEE!

fine/tests/expression/errors/binary_mismatch.fine

@@ -0,0 +1,4 @@
+112 - "twenty five";
+"twenty five" - 112;
+// type-error: 4 cannot apply binary operator '-' to expressions of type 'f64' (on the left) and 'string' (on the right)
+// type-error: 35 cannot apply binary operator '-' to expressions of type 'string' (on the left) and 'f64' (on the right)

fine/tests/expression/errors/if_mismatched_arms.fine

@@ -0,0 +1,2 @@
+if true { "blarg" } else { 23 }
+// type-error: 0 the type of the `then` branch (string) must match the type of the `else` branch (f64)

fine/tests/expression/errors/if_not_bool.fine

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+if 23 { "what" } else { "the" }
+// type-error: 0 conditions must yield a boolean

fine/tests/expression/errors/if_requires_else.fine

@@ -0,0 +1,2 @@
+if (if false { true }) { 32 } else { 23 }
+// type-error: 4 this conditional expression needs an else arm to produce a value

fine/tests/expression/errors/unary_mismatch.fine

@@ -0,0 +1,2 @@
+- "twenty five";
+// type-error: 0 cannot apply unary operator '-' to value of type string