Fixed tests

but I think importing is still not working properly

Cargo.lock

@@ -171,6 +171,11 @@ dependencies = [
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "endian-type"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "failure"
 version = "0.1.5"
@@ -346,6 +351,11 @@ dependencies = [
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "nibble_vec"
+version = "0.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "nix"
 version = "0.14.1"
@@ -517,6 +527,15 @@ dependencies = [
  "proc-macro2 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "radix_trie"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "endian-type 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "nibble_vec 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rand"
 version = "0.4.6"
@@ -735,6 +754,7 @@ dependencies = [
  "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "maplit 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "radix_trie 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "schala-lang-codegen 0.1.0",
  "schala-repl 0.1.0",
  "stopwatch 0.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1005,6 +1025,7 @@ dependencies = [
 "checksum dirs 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3fd78930633bd1c6e35c4b42b1df7b0cbc6bc191146e512bb3bedf243fcc3901"
 "checksum either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "bb1f6b1ce1c140482ea30ddd3335fc0024ac7ee112895426e0a629a6c20adfe3"
 "checksum ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f56c93cc076508c549d9bb747f79aa9b4eb098be7b8cad8830c3137ef52d1e00"
+"checksum endian-type 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c34f04666d835ff5d62e058c3995147c06f42fe86ff053337632bca83e42702d"
 "checksum failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "795bd83d3abeb9220f257e597aa0080a508b27533824adf336529648f6abf7e2"
 "checksum failure_derive 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "ea1063915fd7ef4309e222a5a07cf9c319fb9c7836b1f89b85458672dbb127e1"
 "checksum flate2 0.2.20 (registry+https://github.com/rust-lang/crates.io-index)" = "e6234dd4468ae5d1e2dbb06fe2b058696fdc50a339c68a393aefbf00bc81e423"
@@ -1027,6 +1048,7 @@ dependencies = [
 "checksum memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "88579771288728879b57485cc7d6b07d648c9f0141eb955f8ab7f9d45394468e"
 "checksum miniz-sys 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "1e9e3ae51cea1576ceba0dde3d484d30e6e5b86dee0b2d412fe3a16a15c98202"
 "checksum mortal 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d96ca97d37cb87ea3d658e71c8c2e2f2d420eca5deec047c5a283aa810a900ff"
+"checksum nibble_vec 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "c8d77f3db4bce033f4d04db08079b2ef1c3d02b44e86f25d08886fafa7756ffa"
 "checksum nix 0.14.1 (registry+https://github.com/rust-lang/crates.io-index)" = "6c722bee1037d430d0f8e687bbdbf222f27cc6e4e68d5caf630857bb2b6dbdce"
 "checksum nodrop 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "2f9667ddcc6cc8a43afc9b7917599d7216aa09c463919ea32c59ed6cac8bc945"
 "checksum nom 4.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2ad2a91a8e869eeb30b9cb3119ae87773a8f4ae617f41b1eb9c154b2905f7bd6"
@@ -1046,6 +1068,7 @@ dependencies = [
 "checksum proc-macro2 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "afdc77cc74ec70ed262262942ebb7dac3d479e9e5cfa2da1841c0806f6cdabcc"
 "checksum quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)" = "6ce23b6b870e8f94f81fb0a363d65d86675884b34a09043c81e5562f11c1f8e1"
 "checksum quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "053a8c8bcc71fcce321828dc897a98ab9760bef03a4fc36693c231e5b3216cfe"
+"checksum radix_trie 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "deafbff7bda0a58975ce92723aa18be10eae2e9271f3c3f48de52d131d9f248c"
 "checksum rand 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "552840b97013b1a26992c11eac34bdd778e464601a4c2054b5f0bff7c6761293"
 "checksum rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
 "checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"

schala-lang/language/Cargo.toml

@@ -14,6 +14,7 @@ ena = "0.11.0"
 stopwatch = "0.0.7"
 derivative = "1.0.3"
 colored = "1.8"
+radix_trie = "0.1.5"
 
 schala-lang-codegen = { path = "../codegen" }
 schala-repl = { path = "../../schala-repl" }

schala-lang/language/src/eval.rs

@@ -8,7 +8,7 @@ use itertools::Itertools;
 
 use crate::util::ScopeStack;
 use crate::reduced_ast::{BoundVars, ReducedAST, Stmt, Expr, Lit, Func, Alternative, Subpattern};
-use crate::symbol_table::{SymbolSpec, Symbol, SymbolTable, ScopeSegment, ScopeSegmentKind, FullyQualifiedSymbolName};
+use crate::symbol_table::{SymbolSpec, Symbol, SymbolTable, ScopeSegment, FullyQualifiedSymbolName};
 use crate::builtin::Builtin;
 
 mod test;
@@ -489,6 +489,7 @@ impl<'a> State<'a> {
           Some(Binding { val, .. }) => val.clone(),
           None => return Err(format!("Symbol {} exists in symbol table but not in evaluator table", name))
         }
+        SymbolSpec::Type { name } => return Err(format!("Symbol {} not in scope", name)),
       },
       //TODO ideally this should be returning a runtime error if this is ever None, but it's not
       //handling all bindings correctly yet

schala-lang/language/src/eval/test.rs

@@ -258,3 +258,12 @@ milta()(10)
   "#;
   test_in_fresh_env!(source, "43");
   }
+
+#[test]
+fn import_all() {
+  let source = r#"
+type Option<T> = Some(T) | None
+import Option::*
+let x = Some(9); if x is Some(q) then { q } else { 0 }"#;
+  test_in_fresh_env!(source, "9");
+}

schala-lang/language/src/lib.rs

@@ -18,6 +18,7 @@ extern crate schala_lang_codegen;
 extern crate ena;
 extern crate derivative;
 extern crate colored;
+extern crate radix_trie;
 
 
 macro_rules! bx {

schala-lang/language/src/scope_resolution.rs

@@ -1,6 +1,6 @@
 use std::rc::Rc;
 
-use crate::symbol_table::{SymbolTable, ScopeSegment, ScopeSegmentKind, FullyQualifiedSymbolName};
+use crate::symbol_table::{SymbolTable, ScopeSegment, FullyQualifiedSymbolName};
 use crate::ast::*;
 use crate::util::ScopeStack;
 
@@ -16,17 +16,26 @@ impl<'a> ASTVisitor for ScopeResolver<'a> {
   fn import(&mut self, import_spec: &ImportSpecifier) {
     let ImportSpecifier { ref path_components, ref imported_names, .. } = &import_spec;
     match imported_names {
-      ImportedNames::All => unimplemented!(),
+      ImportedNames::All => {
+        let prefix = FullyQualifiedSymbolName(path_components.iter().map(|c| ScopeSegment {
+          name: c.clone(),
+        }).collect());
+        let members = self.symbol_table.lookup_children_of_fqsn(&prefix);
+        for member in members.into_iter() {
+          let local_name = member.0.last().unwrap().name.clone();
+          self.name_scope_stack.insert(local_name.clone(), member.0);
+        }
+      },
       ImportedNames::LastOfPath => {
         let name = path_components.last().unwrap(); //TODO handle better
         let fqsn_prefix = path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(), kind: ScopeSegmentKind::Type
+          name: c.clone(),
         }).collect();
         self.name_scope_stack.insert(name.clone(), fqsn_prefix);
       }
       ImportedNames::List(ref names) => {
         let fqsn_prefix: FQSNPrefix = path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(), kind: ScopeSegmentKind::Type
+          name: c.clone(),
         }).collect();
         for name in names.iter() {
           self.name_scope_stack.insert(name.clone(), fqsn_prefix.clone());
@@ -70,19 +79,20 @@ impl<'a> ScopeResolver<'a> {
     Ok(())
   }
 
-  //TODO this is incomplete
   fn lookup_name_in_scope(&self, sym_name: &QualifiedName) -> FullyQualifiedSymbolName {
-    let QualifiedName { components: vec, .. } = sym_name;
-    let len = vec.len();
-    let new_vec: Vec<ScopeSegment> = vec.iter().enumerate().map(|(i, name)| {
-      let kind = if i == (len - 1) {
-        ScopeSegmentKind::Terminal
-      } else {
-        ScopeSegmentKind::Type
-      };
-      ScopeSegment { name: name.clone(), kind }
-    }).collect();
-    FullyQualifiedSymbolName(new_vec)
+    let QualifiedName { components, .. } = sym_name;
+    let first_component = &components[0];
+    match self.name_scope_stack.lookup(first_component) {
+      None => {
+        FullyQualifiedSymbolName(components.iter().map(|name| ScopeSegment { name: name.clone() }).collect())
+      },
+      Some(fqsn_prefix) => {
+        let mut full_name = fqsn_prefix.clone();
+        let rest_of_name: FQSNPrefix = components[1..].iter().map(|name| ScopeSegment { name: name.clone() }).collect();
+        full_name.extend_from_slice(&rest_of_name);
+        FullyQualifiedSymbolName(full_name)
+      }
+    }
   }
 
   /// this might be a variable or a pattern. if a variable, set to none

schala-lang/language/src/symbol_table.rs

@@ -8,6 +8,24 @@ use crate::ast;
 use crate::ast::{ItemId, TypeBody, TypeSingletonName, Signature, Statement, StatementKind};
 use crate::typechecking::TypeName;
 
+
+#[allow(unused_macros)]
+macro_rules! fqsn {
+  ( $( $name:expr ; $kind:tt),* ) => {
+    {
+      let mut vec = vec![];
+      $(
+        vec.push(ScopeSegment::new(Rc::new($name.to_string())));
+      )*
+      FullyQualifiedSymbolName(vec)
+    }
+  };
+}
+
+mod symbol_trie;
+use symbol_trie::SymbolTrie;
+mod test;
+
 type LineNumber = u32;
 type SymbolTrackTable = HashMap<Rc<String>, LineNumber>;
 
@@ -27,63 +45,27 @@ impl fmt::Display for FullyQualifiedSymbolName {
 #[derive(Debug, Clone, Eq, PartialEq, Hash, PartialOrd, Ord)]
 pub struct ScopeSegment {
   pub name: Rc<String>, //TODO maybe this could be a &str, for efficiency?
-  pub kind: ScopeSegmentKind,
 }
 
 impl fmt::Display for ScopeSegment {
   fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    use colored::*;
-    use ScopeSegmentKind::*;
-    let kind = match self.kind {
-      Function => "[fn]".green(),
-      Type => "[ty]".red(),
-      Terminal => "[tr]".blue(),
-    };
+    let kind = ""; //TODO implement some kind of kind-tracking here
     write!(f, "{}{}", self.name, kind)
   }
 }
 
 impl ScopeSegment {
-  pub fn new(name: Rc<String>, kind: ScopeSegmentKind) ->  ScopeSegment {
-    ScopeSegment { name, kind }
+  pub fn new(name: Rc<String>) ->  ScopeSegment {
+    ScopeSegment { name }
   }
 }
 
-#[derive(Debug, Clone, Eq, PartialEq, Hash, PartialOrd, Ord)]
-pub enum ScopeSegmentKind {
-  Function,
-  Type,
-  Terminal,
-  //Module
-}
-
-#[allow(unused_macros)]
-macro_rules! fqsn {
-  ( $( $name:expr ; $kind:tt),* ) => {
-    {
-      let mut vec = vec![];
-      $(
-        vec.push(ScopeSegment::new(
-            Rc::new($name.to_string()),  
-            sym_path_kind!($kind),
-        ));
-      )*
-      FullyQualifiedSymbolName(vec)
-    }
-  };
-}
-
-#[allow(unused_macros)]
-macro_rules! sym_path_kind {
-  (fn) => { ScopeSegmentKind::Function };
-  (ty) => { ScopeSegmentKind::Type };
-  (tr) => { ScopeSegmentKind::Terminal };
-}
 
 //cf. p. 150 or so of Language Implementation Patterns
 pub struct SymbolTable {
   symbol_path_to_symbol: HashMap<FullyQualifiedSymbolName, Symbol>,
   id_to_fqsn: HashMap<ItemId, FullyQualifiedSymbolName>,
+  symbol_trie: SymbolTrie,
 }
 
 //TODO add various types of lookups here, maybe multiple hash tables internally?
@@ -92,6 +74,7 @@ impl SymbolTable {
     SymbolTable {
       symbol_path_to_symbol: HashMap::new(),
       id_to_fqsn: HashMap::new(),
+      symbol_trie: SymbolTrie::new()
     }
   }
 
@@ -105,15 +88,20 @@ impl SymbolTable {
 
   fn add_new_symbol(&mut self, local_name: &Rc<String>, scope_path: &Vec<ScopeSegment>, spec: SymbolSpec) {
     let mut vec: Vec<ScopeSegment> = scope_path.clone();
-    vec.push(ScopeSegment { name: local_name.clone(), kind: ScopeSegmentKind::Terminal });
+    vec.push(ScopeSegment { name: local_name.clone() });
     let fully_qualified_name = FullyQualifiedSymbolName(vec);
     let symbol = Symbol { local_name: local_name.clone(), fully_qualified_name: fully_qualified_name.clone(), spec };
+    self.symbol_trie.insert(&fully_qualified_name);
     self.symbol_path_to_symbol.insert(fully_qualified_name, symbol);
   }
 
   pub fn lookup_by_fqsn(&self, fully_qualified_path: &FullyQualifiedSymbolName) -> Option<&Symbol> {
     self.symbol_path_to_symbol.get(fully_qualified_path)
   }
+
+  pub fn lookup_children_of_fqsn(&self, path: &FullyQualifiedSymbolName) -> Vec<FullyQualifiedSymbolName> {
+    self.symbol_trie.get_children(path)
+  }
 }
 
 #[derive(Debug)]
@@ -142,7 +130,10 @@ pub enum SymbolSpec {
     members: HashMap<Rc<String>, TypeName>,
     type_name: TypeName,
   },
-  Binding
+  Binding,
+  Type {
+    name: TypeName
+  },
 }
 
 impl fmt::Display for SymbolSpec {
@@ -153,6 +144,7 @@ impl fmt::Display for SymbolSpec {
       DataConstructor { index, type_name, type_args } => write!(f, "DataConstructor(idx: {})({:?} -> {})", index, type_args, type_name),
       RecordConstructor { type_name, index, ..} => write!(f, "RecordConstructor(idx: {})(<members> -> {})", index, type_name),
       Binding => write!(f, "Binding"),
+      Type { name } => write!(f, "Type <{}>", name),
     }
   }
 }
@@ -197,7 +189,6 @@ impl SymbolTable {
             self.add_function_signature(signature, scope_name_stack)?;
             scope_name_stack.push(ScopeSegment{
               name: signature.name.clone(),
-              kind: ScopeSegmentKind::Function,
             });
             let output = self.add_symbols_from_scope(body, scope_name_stack);
             let _ = scope_name_stack.pop();
@@ -205,7 +196,6 @@ impl SymbolTable {
           },
           TypeDecl { name, body, mutable } => {
             insert_and_check_duplicate_symbol(&mut seen_identifiers, &name.name)?;
-            //TODO add ScopeSegmentKind::Type here
             self.add_type_decl(name, body, mutable, scope_name_stack)?
           },
           Binding { name, .. } => {
@@ -243,9 +233,15 @@ impl SymbolTable {
     use crate::ast::{TypeIdentifier, Variant};
     let TypeBody(variants) = body;
     let ref type_name = type_name.name;
+
+
+    let type_spec = SymbolSpec::Type {
+      name: type_name.clone(),
+    };
+    self.add_new_symbol(type_name, &scope_name_stack, type_spec);
+
     scope_name_stack.push(ScopeSegment{
       name: type_name.clone(),
-      kind: ScopeSegmentKind::Type,
     });
     //TODO figure out why _params isn't being used here
     for (index, var) in variants.iter().enumerate() {
@@ -313,156 +309,3 @@ impl LocalTypeContext {
   }
 }
 
-
-#[cfg(test)]
-mod symbol_table_tests {
-  use super::*;
-  use crate::util::quick_ast;
-
-  macro_rules! values_in_table {
-    //TODO multiple values
-    ($source:expr, $single_value:expr) => {
-      {
-      let mut symbol_table = SymbolTable::new();
-      let ast = quick_ast($source);
-      symbol_table.add_top_level_symbols(&ast).unwrap();
-      match symbol_table.lookup_by_fqsn($single_value) {
-        Some(_spec) => (),
-        None => panic!(),
-      };
-      }
-    }
-  }
-
-  #[test]
-  fn basic_symbol_table() {
-    values_in_table! { "let a = 10; fn b() { 20 }", &fqsn!("b"; tr) }
-  }
-
-  #[test]
-  fn no_duplicates() {
-    let source = r#"
-    fn a() { 1 }
-    fn b() { 2 }
-    fn a() { 3 }
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-
-  #[test]
-  fn no_duplicates_2() {
-    let source = r#"
-    let a = 20;
-    let q = 39;
-    let a = 30;
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-
-  #[test]
-  fn no_duplicates_3() {
-    let source = r#"
-    fn a() {
-      let a = 20
-      let b = 40
-      a + b
-    }
-
-    fn q() {
-      let x = 30
-      let x = 33
-    }
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-
-  #[test]
-  fn dont_falsely_detect_duplicates() {
-    let source = r#"
-    let a = 20;
-    fn some_func() {
-      let a = 40;
-      77
-    }
-    let q = 39;
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    symbol_table.add_top_level_symbols(&ast).unwrap();
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!["a"; tr]).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!["some_func"; fn, "a";tr]).is_some());
-  }
-
-  #[test]
-  fn enclosing_scopes() {
-    let source = r#"
-fn outer_func(x) {
-  fn inner_func(arg) {
-    arg
-  }
-  x + inner_func(x)
-}"#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    symbol_table.add_top_level_symbols(&ast).unwrap();
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
-  }
-
-  #[test]
-  fn enclosing_scopes_2() {
-    let source = r#"
-fn outer_func(x) {
-  fn inner_func(arg) {
-    arg
-  }
-
-  fn second_inner_func() {
-    fn another_inner_func() {
-    }
-  }
-
-  inner_func(x)
-}"#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    symbol_table.add_top_level_symbols(&ast).unwrap();
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; fn, "another_inner_func"; tr)).is_some());
-  }
-
-  #[test]
-  fn enclosing_scopes_3() {
-    let source = r#"
-fn outer_func(x) {
-  fn inner_func(arg) {
-    arg
-  }
-
-  fn second_inner_func() {
-    fn another_inner_func() {
-    }
-    fn another_inner_func() {
-    }
-  }
-
-  inner_func(x)
-}"#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-}
-

schala-lang/language/src/symbol_table/symbol_trie.rs

@@ -0,0 +1,52 @@
+use std::rc::Rc;
+use radix_trie::{Trie, TrieCommon, TrieKey};
+use super::{ScopeSegment, FullyQualifiedSymbolName};
+use std::hash::{Hasher, Hash};
+use std::collections::hash_map::DefaultHasher;
+
+#[derive(Debug)]
+pub struct SymbolTrie(Trie<FullyQualifiedSymbolName, ()>);
+
+impl TrieKey for FullyQualifiedSymbolName {
+  fn encode_bytes(&self) -> Vec<u8> {
+    let mut hasher = DefaultHasher::new();
+    let mut output = vec![];
+    let FullyQualifiedSymbolName(scopes) = self;
+    for segment in scopes.iter() {
+      segment.name.as_bytes().hash(&mut hasher);
+      output.extend_from_slice(&hasher.finish().to_be_bytes());
+    }
+    output
+  }
+}
+
+impl SymbolTrie {
+  pub fn new() -> SymbolTrie {
+    SymbolTrie(Trie::new())
+  }
+
+  pub fn insert(&mut self, fqsn: &FullyQualifiedSymbolName) {
+    self.0.insert(fqsn.clone(), ());
+  }
+
+  pub fn get_children(&self, fqsn: &FullyQualifiedSymbolName) -> Vec<FullyQualifiedSymbolName> {
+    let subtrie = match self.0.subtrie(fqsn) {
+      Some(s) => s,
+      None => return vec![]
+    };
+    let output: Vec<FullyQualifiedSymbolName> = subtrie.keys().filter(|cur_key| **cur_key != *fqsn).map(|fqsn| fqsn.clone()).collect();
+    output
+  }
+}
+
+#[test]
+fn test_trie_insertion() {
+  let mut trie = SymbolTrie::new();
+
+  trie.insert(&fqsn!("unrelated"; ty, "thing"; tr));
+  trie.insert(&fqsn!("outer"; ty, "inner"; tr));
+  trie.insert(&fqsn!("outer"; ty, "inner"; ty, "still_inner"; tr));
+
+  let children = trie.get_children(&fqsn!("outer"; ty, "inner"; tr));
+  assert_eq!(children.len(), 1);
+}

schala-lang/language/src/symbol_table/test.rs

@@ -0,0 +1,159 @@
+#![cfg(test)]
+
+#[macro_use]
+use super::*;
+use crate::util::quick_ast;
+
+macro_rules! values_in_table {
+  ($source:literal, $single_value:expr) => {
+    values_in_table!($source | $single_value);
+  };
+  ($source:literal | $( $value:expr ),* ) => {
+    {
+    let mut symbol_table = SymbolTable::new();
+    let ast = quick_ast($source);
+    symbol_table.add_top_level_symbols(&ast).unwrap();
+    $(
+      match symbol_table.lookup_by_fqsn($value) {
+        Some(_spec) => (),
+        None => panic!(),
+      };
+    )*
+    }
+  };
+}
+
+#[test]
+fn basic_symbol_table() {
+  values_in_table! { "let a = 10; fn b() { 20 }", &fqsn!("b"; tr) };
+  values_in_table! { "type Option<T> = Some(T) | None" |
+    &fqsn!("Option"; tr),
+    &fqsn!("Option"; ty, "Some"; tr),
+    &fqsn!("Option"; ty, "None"; tr) };
+}
+
+#[test]
+fn no_duplicates() {
+  let source = r#"
+  fn a() { 1 }
+  fn b() { 2 }
+  fn a() { 3 }
+  "#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
+  assert!(output.contains("Duplicate"))
+}
+
+#[test]
+fn no_duplicates_2() {
+  let source = r#"
+  let a = 20;
+  let q = 39;
+  let a = 30;
+  "#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
+  assert!(output.contains("Duplicate"))
+}
+
+#[test]
+fn no_duplicates_3() {
+  let source = r#"
+  fn a() {
+    let a = 20
+    let b = 40
+    a + b
+  }
+
+  fn q() {
+    let x = 30
+    let x = 33
+  }
+  "#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
+  assert!(output.contains("Duplicate"))
+}
+
+#[test]
+fn dont_falsely_detect_duplicates() {
+  let source = r#"
+  let a = 20;
+  fn some_func() {
+    let a = 40;
+    77
+  }
+  let q = 39;
+  "#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  symbol_table.add_top_level_symbols(&ast).unwrap();
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!["a"; tr]).is_some());
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!["some_func"; fn, "a";tr]).is_some());
+}
+
+#[test]
+fn enclosing_scopes() {
+  let source = r#"
+fn outer_func(x) {
+fn inner_func(arg) {
+  arg
+}
+x + inner_func(x)
+}"#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  symbol_table.add_top_level_symbols(&ast).unwrap();
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
+}
+
+#[test]
+fn enclosing_scopes_2() {
+  let source = r#"
+fn outer_func(x) {
+fn inner_func(arg) {
+  arg
+}
+
+fn second_inner_func() {
+  fn another_inner_func() {
+  }
+}
+
+inner_func(x)
+}"#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  symbol_table.add_top_level_symbols(&ast).unwrap();
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; tr)).is_some());
+  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; fn, "another_inner_func"; tr)).is_some());
+}
+
+#[test]
+fn enclosing_scopes_3() {
+  let source = r#"
+fn outer_func(x) {
+fn inner_func(arg) {
+  arg
+}
+
+fn second_inner_func() {
+  fn another_inner_func() {
+  }
+  fn another_inner_func() {
+  }
+}
+
+inner_func(x)
+}"#;
+  let mut symbol_table = SymbolTable::new();
+  let ast = quick_ast(source);
+  let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
+  assert!(output.contains("Duplicate"))
+}