From 5491b5581f9bb26c33e3f432c58b71b3cc401216 Mon Sep 17 00:00:00 2001
From: Yuya Nishihara <yuya@tcha.org>
Date: Wed, 16 Nov 2022 20:46:53 +0900
Subject: [PATCH] revset: decouple prefix/infix/postfix range operators

This unblocks the use of PrattParser, which builds an operator map keyed
solely by Rule, not by (Rule, prefix/infix/postfix) pair.
---
 lib/src/revset.pest | 10 ++++++++--
 lib/src/revset.rs   |  6 +++---
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/lib/src/revset.pest b/lib/src/revset.pest
index 369f2c69b..f0081938a 100644
--- a/lib/src/revset.pest
+++ b/lib/src/revset.pest
@@ -28,8 +28,14 @@ parents_op = { "-" }
 children_op = { "+" }
 
 dag_range_op = { ":" }
+dag_range_pre_op = { ":" }
+dag_range_post_op = { ":" }
 range_op = { ".." }
+range_pre_op = { ".." }
+range_post_op = { ".." }
 range_ops = _{ dag_range_op | range_op }
+range_pre_ops = _{ dag_range_pre_op | range_pre_op }
+range_post_ops = _{ dag_range_post_op | range_post_op }
 
 union_op = { "|" }
 intersection_op = { "&" }
@@ -52,8 +58,8 @@ neighbors_expression = { primary ~ (parents_op | children_op)* }
 
 range_expression = {
   neighbors_expression ~ range_ops ~ neighbors_expression
-  | neighbors_expression ~ range_ops
-  | range_ops ~ neighbors_expression
+  | neighbors_expression ~ range_post_ops
+  | range_pre_ops ~ neighbors_expression
   | neighbors_expression
 }
 
diff --git a/lib/src/revset.rs b/lib/src/revset.rs
index 8e6791293..7fbe7fcb8 100644
--- a/lib/src/revset.rs
+++ b/lib/src/revset.rs
@@ -518,7 +518,7 @@ fn parse_range_expression_rule(
 ) -> Result<Rc<RevsetExpression>, RevsetParseError> {
     let first = pairs.next().unwrap();
     match first.as_rule() {
-        Rule::dag_range_op | Rule::range_op => {
+        Rule::dag_range_pre_op | Rule::range_pre_op => {
             return Ok(parse_neighbors_expression_rule(
                 pairs.next().unwrap().into_inner(),
                 workspace_ctx,
@@ -535,7 +535,7 @@ fn parse_range_expression_rule(
     let mut expression = parse_neighbors_expression_rule(first.into_inner(), workspace_ctx)?;
     if let Some(next) = pairs.next() {
         match next.as_rule() {
-            Rule::dag_range_op => {
+            Rule::dag_range_op | Rule::dag_range_post_op => {
                 if let Some(heads_pair) = pairs.next() {
                     let heads_expression =
                         parse_neighbors_expression_rule(heads_pair.into_inner(), workspace_ctx)?;
@@ -544,7 +544,7 @@ fn parse_range_expression_rule(
                     expression = expression.descendants();
                 }
             }
-            Rule::range_op => {
+            Rule::range_op | Rule::range_post_op => {
                 if let Some(heads_pair) = pairs.next() {
                     let heads_expression =
                         parse_neighbors_expression_rule(heads_pair.into_inner(), workspace_ctx)?;