Make try without catch/finally an error

src/parser.jl

@@ -2213,7 +2213,7 @@ function parse_try(ps)
         bump(ps, TRIVIA_FLAG)
         parse_block(ps)
         if !has_catch
-            #v1.8: try else end ==> (try (block) false false (error (block)) false)
+            #v1.8: try else x finally y end ==> (try (block) false false (error (block x)) (block y))
             emit(ps, else_mark, K"error", error="Expected `catch` before `else`")
         end
         #v1.7: try catch ; else end ==> (try (block) false (block) (error (block)) false)
@@ -2241,6 +2241,10 @@ function parse_try(ps)
         emit_diagnostic(ps, m, position(ps),
                         warning="`catch` after `finally` will execute out of order")
     end
+    if !has_catch && !has_finally
+        # try x end  ==>  (try (block x) false false false false (error-t))
+        bump_invisible(ps, K"error", TRIVIA_FLAG, error="try without catch or finally")
+    end
     bump_closing_token(ps, K"end")
     emit(ps, mark, out_kind, flags)
 end

test/parser.jl

@@ -558,11 +558,12 @@ tests = [
         "try x finally y end"   =>  "(try (block x) false false false (block y))"
         # v1.8 only
         ((v=v"1.8",), "try catch ; else end") => "(try (block) false (block) (block) false)"
-        ((v=v"1.8",), "try else end") => "(try (block) false false (error (block)) false)"
+        ((v=v"1.8",), "try else x finally y end") => "(try (block) false false (error (block x)) (block y))"
         ((v=v"1.7",), "try catch ; else end")  =>  "(try (block) false (block) (error (block)) false)"
         # finally before catch :-(
         "try x finally y catch e z end"  =>  "(try_finally_catch (block x) false false false (block y) e (block z))" =>
             Expr(:try, Expr(:block, :x), :e, Expr(:block, :z), Expr(:block, :y))
+        "try x end" => "(try (block x) false false false false (error-t))"
     ],
     JuliaSyntax.parse_imports => [
         "import A as B: x"  => "(import (: (error (as (. A) B)) (. x)))"