From 9b1595b795121d233cd0cf32537661839e318914 Mon Sep 17 00:00:00 2001
From: Jesse Luehrs <doy@tozt.net>
Date: Mon, 17 Jan 2022 01:19:08 -0500
Subject: basic subshell implementation

---
 src/parse/ast.rs  | 31 ++++++++++++++++++++++++++++++-
 src/runner/mod.rs |  4 ++++
 src/shell.pest    |  6 ++++--
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/parse/ast.rs b/src/parse/ast.rs
index bac40c8..9d74331 100644
--- a/src/parse/ast.rs
+++ b/src/parse/ast.rs
@@ -141,7 +141,36 @@ impl Exe {
     }
 
     fn build_ast(pair: pest::iterators::Pair<Rule>) -> Self {
-        assert!(matches!(pair.as_rule(), Rule::exe));
+        assert!(matches!(pair.as_rule(), Rule::subshell | Rule::exe));
+        if matches!(pair.as_rule(), Rule::subshell) {
+            return Self {
+                exe: Word {
+                    parts: vec![WordPart::SingleQuoted(
+                        std::env::current_exe()
+                            .unwrap()
+                            .to_str()
+                            .unwrap()
+                            .to_string(),
+                    )],
+                },
+                args: vec![
+                    Word {
+                        parts: vec![WordPart::SingleQuoted("-c".to_string())],
+                    },
+                    Word {
+                        parts: vec![WordPart::SingleQuoted(
+                            pair.as_str()
+                                .strip_prefix('(')
+                                .unwrap()
+                                .strip_suffix(')')
+                                .unwrap()
+                                .to_string(),
+                        )],
+                    },
+                ],
+                redirects: vec![],
+            };
+        }
         let mut iter = pair.into_inner();
         let exe = match WordOrRedirect::build_ast(iter.next().unwrap()) {
             WordOrRedirect::Word(word) => word,
diff --git a/src/runner/mod.rs b/src/runner/mod.rs
index 98894b3..63af51b 100644
--- a/src/runner/mod.rs
+++ b/src/runner/mod.rs
@@ -158,7 +158,11 @@ async fn run_commands(
                         *should = !list.is_empty();
                         if *should {
                             let val = list.remove(0);
+                            // XXX i really need to just pick one location and
+                            // stick with it instead of trying to keep these
+                            // in sync
                             env.set_var(var, &val);
+                            std::env::set_var(var, &val);
                         }
                     } else {
                         unreachable!();
diff --git a/src/shell.pest b/src/shell.pest
index 8a51070..fdfb1b1 100644
--- a/src/shell.pest
+++ b/src/shell.pest
@@ -3,7 +3,8 @@ escape_char       = @{ "\\" ~ ANY }
 
 bareword_char = @{
     escape_char |
-    !("|" | ";" | "\"" | "'" | "$" | "{" | WHITESPACE | COMMENT) ~ ANY
+    !("|" | ";" | "\"" | "'" | "$" | "{" | "(" | ")" | WHITESPACE | COMMENT)
+        ~ ANY
 }
 single_string_char = @{ basic_escape_char | (!"'" ~ ANY) }
 double_string_char = @{ escape_char | (!("\"" | "$") ~ ANY) }
@@ -44,8 +45,9 @@ word = ${ word_part+ }
 word_or_redirect = ${ redir_prefix? ~ word }
 
 exe      = ${ word_or_redirect ~ (w ~ word_or_redirect)* }
+subshell = ${ "(" ~ w? ~ commands ~ w? ~ ")" }
 list     = ${ word ~ (w ~ word)* }
-pipeline = ${ exe ~ (w? ~ "|" ~ w? ~ exe)* }
+pipeline = ${ (subshell | exe) ~ (w? ~ "|" ~ w? ~ (subshell | exe))* }
 
 control_if    = ${ "if" ~ w ~ pipeline }
 control_while = ${ "while" ~ w ~ pipeline }
-- 
cgit v1.2.3-54-g00ecf