Add a test case for close-calls on all-real arithmetic expressions.

collects/tests/typed-scheme/optimizer/close-calls/all-real.rkt

@@ -0,0 +1,25 @@
+#;
+(
+ all-real.rkt 24:0 (#%app + (quote 3) (quote 4)) -- binary, args all float-arg-expr, return type not Float -- caused by: 24:8 (quote 3)
+ all-real.rkt 25:0 (#%app * (quote 3) (quote 4)) -- binary, args all float-arg-expr, return type not Float -- caused by: 25:8 (quote 3)
+ 7
+ 12
+ )
+
+#lang typed/racket
+
+;; all-real expressions
+;; They currently get reported as missed float optimizations.
+;; Whether that's the right thing or not is debatable.
+;; pro: more often than not, Real types pop up when the type system can't
+;;      prove something, but the user really wants a float type, so reporting
+;;      is likely to be helpful
+;; con: all-real expressions can arise from integer-only computations
+;;      (ex: (+ (sqrt 4) 2) : Positive-Real), so reporting a missed float opt
+;;      sounds wrong
+;; If we decide against reporting these cases in the future, it's only a matter
+;; of adding a check to make sure at least one of the subexpressions is in the
+;; Float layer in addition to the entire expression being in the Real layer.
+
+(+ (ann 3 Real) (ann 4 Real))
+(* (ann 3 Real) (ann 4 Real))