feat(hydroflow_lang): improve singleton error messages/handling (#1133)

hydroflow/tests/compile-fail/surface_singleton_nostate.rs

@@ -0,0 +1,10 @@
+pub fn main() {
+    let mut df = hydroflow::hydroflow_syntax! {
+        my_ref = source_iter(15..=25) -> null();
+        source_iter(10..=30)
+            -> filter(|value| value <= #my_ref.as_reveal_ref())
+            -> null();
+
+    };
+    df.run_available();
+}

hydroflow/tests/compile-fail/surface_singleton_nostate.stderr

@@ -0,0 +1,20 @@
+error[E0425]: cannot find value `singleton_op_2v1` in this scope
+ --> tests/compile-fail/surface_singleton_nostate.rs:5:16
+  |
+5 |             -> filter(|value| value <= #my_ref.as_reveal_ref())
+  |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
+
+error[E0282]: type annotations needed
+ --> tests/compile-fail/surface_singleton_nostate.rs:2:18
+  |
+2 |       let mut df = hydroflow::hydroflow_syntax! {
+  |  __________________^
+3 | |         my_ref = source_iter(15..=25) -> null();
+4 | |         source_iter(10..=30)
+5 | |             -> filter(|value| value <= #my_ref.as_reveal_ref())
+6 | |             -> null();
+7 | |
+8 | |     };
+  | |_____^ cannot infer type
+  |
+  = note: this error originates in the macro `hydroflow::hydroflow_syntax` (in Nightly builds, run with -Z macro-backtrace for more info)

hydroflow/tests/compile-fail/surface_singleton_nostate_undefined.rs

@@ -0,0 +1,9 @@
+pub fn main() {
+    let mut df = hydroflow::hydroflow_syntax! {
+        my_ref = source_iter(15..=25) -> null();
+        source_iter(10..=30)
+            -> filter(|value| value <= #my_ref.as_reveal_ref() && value <= #unknown.as_reveal_ref())
+            -> null();
+    };
+    df.run_available();
+}

hydroflow/tests/compile-fail/surface_singleton_nostate_undefined.stderr

@@ -0,0 +1,5 @@
+error: Cannot find referenced name `unknown`; name was never assigned.
+ --> tests/compile-fail/surface_singleton_nostate_undefined.rs:5:77
+  |
+5 |             -> filter(|value| value <= #my_ref.as_reveal_ref() && value <= #unknown.as_reveal_ref())
+  |                                                                             ^^^^^^^

hydroflow/tests/compile-fail/surface_singleton_undefined.rs

@@ -0,0 +1,9 @@
+pub fn main() {
+    let mut df = hydroflow::hydroflow_syntax! {
+        source_iter(10..=30)
+            -> filter(|value| value <= #unknown.as_reveal_ref())
+            -> null();
+
+    };
+    df.run_available();
+}

hydroflow/tests/compile-fail/surface_singleton_undefined.stderr

@@ -0,0 +1,5 @@
+error: Cannot find referenced name `unknown`; name was never assigned.
+ --> tests/compile-fail/surface_singleton_undefined.rs:4:41
+  |
+4 |             -> filter(|value| value <= #unknown.as_reveal_ref())
+  |                                         ^^^^^^^

hydroflow/tests/compile-fail/surface_singleton_undefined_nostate.rs

@@ -0,0 +1,9 @@
+pub fn main() {
+    let mut df = hydroflow::hydroflow_syntax! {
+        my_ref = source_iter(15..=25) -> null();
+        source_iter(10..=30)
+            -> filter(|value| value <= #unknown.as_reveal_ref() && value <= #my_ref.as_reveal_ref())
+            -> null();
+    };
+    df.run_available();
+}

hydroflow/tests/compile-fail/surface_singleton_undefined_nostate.stderr

@@ -0,0 +1,5 @@
+error: Cannot find referenced name `unknown`; name was never assigned.
+ --> tests/compile-fail/surface_singleton_undefined_nostate.rs:5:41
+  |
+5 |             -> filter(|value| value <= #unknown.as_reveal_ref() && value <= #my_ref.as_reveal_ref())
+  |                                         ^^^^^^^

hydroflow/tests/compile-fail/surface_undefined_variable.stderr → hydroflow/tests/compile-fail/surface_varname_undefined.stderr

@@ -1,11 +1,11 @@
 error: Cannot find name `hydro_lab`; name was never assigned.
- --> tests/compile-fail/surface_undefined_variable.rs:5:9
+ --> tests/compile-fail/surface_varname_undefined.rs:5:9
   |
 5 |         hydro_lab -> for_each(std::mem::drop);
   |         ^^^^^^^^^
 
 error: `for_each` must have exactly 1 input(s), actually has 0.
- --> tests/compile-fail/surface_undefined_variable.rs:5:22
+ --> tests/compile-fail/surface_varname_undefined.rs:5:22
   |
 5 |         hydro_lab -> for_each(std::mem::drop);
   |                      ^^^^^^^^^^^^^^^^^^^^^^^^

hydroflow_lang/src/graph/flat_graph_builder.rs

@@ -368,8 +368,19 @@ impl FlatGraphBuilder {
                             .and_then(|result| result.as_ref().ok())
                             .and_then(|ends| ends.out.as_ref())
                             .cloned();
-                        let (_port, node_id) = self.helper_resolve_name(port_det, false)?;
-                        Some(node_id)
+                        if let Some((_port, node_id)) = self.helper_resolve_name(port_det, false) {
+                            Some(node_id)
+                        } else {
+                            self.diagnostics.push(Diagnostic::spanned(
+                                singleton_ref.span(),
+                                Level::Error,
+                                format!(
+                                    "Cannot find referenced name `{}`; name was never assigned.",
+                                    singleton_ref
+                                ),
+                            ));
+                            None
+                        }
                     })
                     .collect();