From def5884b59495fbe3ff199f199eee58731f5398e Mon Sep 17 00:00:00 2001
From: Max Brunsfeld <maxbrunsfeld@gmail.com>
Date: Mon, 14 Jan 2019 14:07:42 -0800
Subject: [PATCH] Allow passing grammar JS or JSON path to `generate` command

---
 cli/src/generate/mod.rs        | 12 +++++++++++-
 cli/src/generate/properties.rs | 22 ++++++++++++----------
 cli/src/main.rs                |  3 +++
 3 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/cli/src/generate/mod.rs b/cli/src/generate/mod.rs
index 283ab0b2..1593c0da 100644
--- a/cli/src/generate/mod.rs
+++ b/cli/src/generate/mod.rs
@@ -28,12 +28,14 @@ lazy_static! {
 
 pub fn generate_parser_in_directory(
     repo_path: &PathBuf,
+    grammar_path: Option<&str>,
     minimize: bool,
     state_ids_to_log: Vec<usize>,
     properties_only: bool,
 ) -> Result<()> {
     if !properties_only {
-        let grammar_json = load_js_grammar_file(&repo_path.join("grammar.js"));
+        let grammar_path = grammar_path.map_or(repo_path.join("grammar.js"), |s| s.into());
+        let grammar_json = load_grammar_file(&grammar_path);
         let c_code =
             generate_parser_for_grammar_with_opts(&grammar_json, minimize, state_ids_to_log)?;
         fs::create_dir_all("src")?;
@@ -77,6 +79,14 @@ fn generate_parser_for_grammar_with_opts(
     ))
 }
 
+fn load_grammar_file(grammar_path: &PathBuf) -> String {
+    match grammar_path.extension().and_then(|e| e.to_str()) {
+        Some("js") => load_js_grammar_file(grammar_path),
+        Some("json") => fs::read_to_string(grammar_path).expect("Failed to read grammar file"),
+        _ => panic!("Unknown grammar file extension"),
+    }
+}
+
 fn load_js_grammar_file(grammar_path: &PathBuf) -> String {
     let mut node_process = Command::new("node")
         .stdin(Stdio::piped())
diff --git a/cli/src/generate/properties.rs b/cli/src/generate/properties.rs
index cca7fef8..e1492d6f 100644
--- a/cli/src/generate/properties.rs
+++ b/cli/src/generate/properties.rs
@@ -424,16 +424,18 @@ pub fn generate_property_sheets(repo_path: &Path) -> Result<()> {
     let src_dir_path = repo_path.join("src");
     let properties_dir_path = repo_path.join("properties");
 
-    for entry in fs::read_dir(properties_dir_path)? {
-        let css_path = entry?.path();
-        let css = fs::read_to_string(&css_path)?;
-        let sheet = generate_property_sheet(&css_path, &css)?;
-        let property_sheet_json_path = src_dir_path
-            .join(css_path.file_name().unwrap())
-            .with_extension("json");
-        let property_sheet_json_file = File::create(property_sheet_json_path)?;
-        let mut writer = BufWriter::new(property_sheet_json_file);
-        serde_json::to_writer_pretty(&mut writer, &sheet)?;
+    if let Ok(entries) = fs::read_dir(properties_dir_path) {
+        for entry in entries {
+            let css_path = entry?.path();
+            let css = fs::read_to_string(&css_path)?;
+            let sheet = generate_property_sheet(&css_path, &css)?;
+            let property_sheet_json_path = src_dir_path
+                .join(css_path.file_name().unwrap())
+                .with_extension("json");
+            let property_sheet_json_file = File::create(property_sheet_json_path)?;
+            let mut writer = BufWriter::new(property_sheet_json_file);
+            serde_json::to_writer_pretty(&mut writer, &sheet)?;
+        }
     }
 
     Ok(())
diff --git a/cli/src/main.rs b/cli/src/main.rs
index 5a830458..80a40758 100644
--- a/cli/src/main.rs
+++ b/cli/src/main.rs
@@ -43,6 +43,7 @@ fn run() -> error::Result<()> {
         .subcommand(
             SubCommand::with_name("generate")
                 .about("Generate a parser")
+                .arg(Arg::with_name("grammar-path").index(1))
                 .arg(Arg::with_name("log").long("log"))
                 .arg(Arg::with_name("properties-only").long("properties"))
                 .arg(
@@ -84,6 +85,7 @@ fn run() -> error::Result<()> {
             logger::init();
         }
 
+        let grammar_path = matches.value_of("grammar-path");
         let minimize = !matches.is_present("no-minimize");
         let properties_only = matches.is_present("properties-only");
         let state_ids_to_log = matches
@@ -94,6 +96,7 @@ fn run() -> error::Result<()> {
             });
         generate::generate_parser_in_directory(
             &current_dir,
+            grammar_path,
             minimize,
             state_ids_to_log,
             properties_only,