lang: parse pipelines

crates/lang/src/lst_parser/grammar/expression/pipeline.rs

@@ -0,0 +1,36 @@
+use enumset::enum_set;
+
+use crate::lst_parser::{
+    error::SyntaxError,
+    syntax_kind::{SyntaxKind::*, TokenSet},
+    CompletedMarker, Parser,
+};
+
+use super::expression;
+
+pub fn pipeline(p: &mut Parser, start_expr: CompletedMarker) -> Option<CompletedMarker> {
+    if !pipe(p) {
+        return Some(start_expr);
+    }
+    let pipeline_marker = start_expr.precede(p, "pipeline_start");
+
+    loop {
+        if expression(p, true).is_none() {
+            return Some(pipeline_marker.complete_err(p, SyntaxError::PipelineNeedsSink));
+        }
+        if !pipe(p) {
+            return Some(pipeline_marker.complete(p, PIPELINE));
+        }
+    }
+}
+
+pub const PIPES: TokenSet = enum_set!(PIPE | MAPPING_PIPE | NULL_PIPE);
+
+fn pipe(p: &mut Parser) -> bool {
+    if PIPES.contains(p.current()) {
+        p.do_bump();
+        true
+    } else {
+        false
+    }
+}