Reorganize tests and benchmark scripts.

Mainly to get rid of one top level directory. But this will
also be useful when there are tests of the embedding API.

test/language/if/dangling_else.wren

@@ -0,0 +1,3 @@
+// A dangling else binds to the right-most if.
+if (true) if (false) IO.print("bad") else IO.print("good") // expect: good
+if (false) if (true) IO.print("bad") else IO.print("bad")

test/language/if/else.wren

@@ -0,0 +1,6 @@
+// Evaluate the 'else' expression if the condition is false.
+if (true) IO.print("good") else IO.print("bad") // expect: good
+if (false) IO.print("bad") else IO.print("good") // expect: good
+
+// Allow block body.
+if (false) null else { IO.print("block") } // expect: block

test/language/if/if.wren

@@ -0,0 +1,10 @@
+// Evaluate the 'then' expression if the condition is true.
+if (true) IO.print("good") // expect: good
+if (false) IO.print("bad")
+
+// Allow block body.
+if (true) { IO.print("block") } // expect: block
+
+// Assignment in if condition.
+var a = false
+if (a = true) IO.print(a) // expect: true

test/language/if/newline_after_else.wren

@@ -0,0 +1 @@
+if (true) "ok" else // expect error

test/language/if/newline_after_if.wren

@@ -0,0 +1,2 @@
+if // expect error
+(true) IO.print("bad")

test/language/if/truth.wren

@@ -0,0 +1,8 @@
+// False and null are false.
+if (false) IO.print("bad") else IO.print("false") // expect: false
+if (null) IO.print("bad") else IO.print("null") // expect: null
+
+// Everything else is true.
+if (true) IO.print(true) // expect: true
+if (0) IO.print(0) // expect: 0
+if ("") IO.print("empty") // expect: empty