From a3ae75d66fec8cd76f734b9dc7146ffcc219f431 Mon Sep 17 00:00:00 2001
From: James Harton <james@automat.nz>
Date: Thu, 6 Sep 2018 18:02:55 +1200
Subject: [PATCH] Tidy up grammar around method predicates and exploders.

---
 parser/src/grammar.pest         |  7 +++---
 parser/src/grammar/test/call.rs | 38 +++++++++++++++++++++++++++++++++
 parser/src/grammar/test/def.rs  | 18 ++++++++++++++++
 3 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/parser/src/grammar.pest b/parser/src/grammar.pest
index 9163de2..6e22677 100644
--- a/parser/src/grammar.pest
+++ b/parser/src/grammar.pest
@@ -140,8 +140,7 @@ def_type                    =  { "deftype" }
 def_impl                    =  { "defimpl" }
 def_name                    = ${ identifier ~ def_modifier? }
 def_predicate               =  { "?" }
-def_bang                    =  { "!" }
-def_modifier                = _{ def_predicate | def_bang }
+def_modifier                = _{ def_predicate }
 def_return_type             =  { "<" ~ variable ~ ">" }
 def_fn                      = _{ def_fn_keyword ~ def_return_type? ~ def_name ~ argument_list? }
 def_ty                      = _{ def_type_keyword ~ def_name ~ argument_list? }
@@ -207,6 +206,8 @@ unary_operator              = _{ plus | minus | logical_not }
 call_test                   = _{ soi ~ call ~ eoi }
 call                        = ${ call_receiver ~ "." ~ call_message ~ call_arguments }
 call_receiver               =  { identifier }
-call_message                =  { identifier }
+call_message                =  ${ identifier ~ (call_predicate | call_bang)? }
+call_predicate              =  { "?" }
+call_bang                   =  { "!" }
 call_arguments              = !{ "(" ~ (call_argument ~ ("," ~ call_argument)*)? ~ ")" }
 call_argument               =  { expression }
diff --git a/parser/src/grammar/test/call.rs b/parser/src/grammar/test/call.rs
index 642848f..0baabd3 100644
--- a/parser/src/grammar/test/call.rs
+++ b/parser/src/grammar/test/call.rs
@@ -34,3 +34,41 @@ fn call_with_args() {
         ]
     )
 }
+
+#[test]
+fn call_with_predicate() {
+    parses_to!(
+        parser: Grammar,
+        input: "marty.mcfly?()",
+        rule: Rule::call_test,
+        tokens: [
+            call(0, 14, [
+                call_receiver(0, 5, [identifier(0, 5)]),
+                call_message(6, 12, [
+                    identifier(6, 11),
+                    call_predicate(11, 12)
+                ]),
+                call_arguments(12, 14)
+            ])
+        ]
+    )
+}
+
+#[test]
+fn call_with_explosion() {
+    parses_to!(
+        parser: Grammar,
+        input: "marty.mcfly!()",
+        rule: Rule::call_test,
+        tokens: [
+            call(0, 14, [
+                call_receiver(0, 5, [identifier(0, 5)]),
+                call_message(6, 12, [
+                    identifier(6, 11),
+                    call_bang(11, 12)
+                ]),
+                call_arguments(12, 14)
+            ])
+        ]
+    )
+}
diff --git a/parser/src/grammar/test/def.rs b/parser/src/grammar/test/def.rs
index 08b7bd7..6cb3728 100644
--- a/parser/src/grammar/test/def.rs
+++ b/parser/src/grammar/test/def.rs
@@ -133,6 +133,24 @@ fn define_constructor() {
     )
 }
 
+#[test]
+fn define_function_with_predicate() {
+    parses_to!(
+        parser: Grammar,
+        input: "defp name?",
+        rule: Rule::def_test,
+        tokens: [
+            def(0, 10, [
+                def_private(0, 4),
+                def_name(5, 10, [
+                    identifier(5, 9),
+                    def_predicate(9, 10),
+                ])
+            ])
+        ]
+    )
+}
+
 #[test]
 fn def_trait_type_only() {
     parses_to!(