Merge pull request #89 from kubouch/hide-import-patterns

Add import patterns to 'hide'

crates/nu-parser/src/parse_keywords.rs

@@ -600,12 +600,90 @@ pub fn parse_hide(
         let (name_expr, err) = parse_string(working_set, spans[1]);
         error = error.or(err);
 
-        let name_bytes: Vec<u8> = working_set.get_span_contents(spans[1]).into();
+        let (import_pattern, err) = parse_import_pattern(working_set, spans[1]);
+        error = error.or(err);
 
-        // TODO: Do the import pattern stuff for bulk-hiding
+        let exported_names: Vec<Vec<u8>> =
+            if let Some(block_id) = working_set.find_module(&import_pattern.head) {
+                working_set
+                    .get_block(block_id)
+                    .exports
+                    .iter()
+                    .map(|(name, _)| name.clone())
+                    .collect()
+            } else if import_pattern.members.is_empty() {
+                // The pattern head can be e.g. a function name, not just a module
+                vec![import_pattern.head.clone()]
+            } else {
+                return (
+                    garbage_statement(spans),
+                    Some(ParseError::ModuleNotFound(spans[1])),
+                );
+            };
 
-        if working_set.hide_decl(&name_bytes).is_none() {
-            error = error.or_else(|| Some(ParseError::UnknownCommand(spans[1])));
+        // This kind of inverts the import pattern matching found in parse_use()
+        let names_to_hide = if import_pattern.members.is_empty() {
+            exported_names
+        } else {
+            match &import_pattern.members[0] {
+                ImportPatternMember::Glob { .. } => exported_names
+                    .into_iter()
+                    .map(|name| {
+                        let mut new_name = import_pattern.head.to_vec();
+                        new_name.push(b'.');
+                        new_name.extend(&name);
+                        new_name
+                    })
+                    .collect(),
+                ImportPatternMember::Name { name, span } => {
+                    let new_exports: Vec<Vec<u8>> = exported_names
+                        .into_iter()
+                        .filter(|n| n == name)
+                        .map(|n| {
+                            let mut new_name = import_pattern.head.to_vec();
+                            new_name.push(b'.');
+                            new_name.extend(&n);
+                            new_name
+                        })
+                        .collect();
+
+                    if new_exports.is_empty() {
+                        error = error.or(Some(ParseError::ExportNotFound(*span)))
+                    }
+
+                    new_exports
+                }
+                ImportPatternMember::List { names } => {
+                    let mut output = vec![];
+
+                    for (name, span) in names {
+                        let mut new_exports: Vec<Vec<u8>> = exported_names
+                            .iter()
+                            .filter_map(|n| if n == name { Some(n.clone()) } else { None })
+                            .map(|n| {
+                                let mut new_name = import_pattern.head.to_vec();
+                                new_name.push(b'.');
+                                new_name.extend(n);
+                                new_name
+                            })
+                            .collect();
+
+                        if new_exports.is_empty() {
+                            error = error.or(Some(ParseError::ExportNotFound(*span)))
+                        } else {
+                            output.append(&mut new_exports)
+                        }
+                    }
+
+                    output
+                }
+            }
+        };
+
+        for name in names_to_hide {
+            if working_set.hide_decl(&name).is_none() {
+                error = error.or_else(|| Some(ParseError::UnknownCommand(spans[1])));
+            }
         }
 
         // Create the Hide command call

crates/nu-protocol/src/engine/engine_state.rs

@@ -375,7 +375,7 @@ impl<'a> StateWorkingSet<'a> {
 
             if let Some(decl_id) = scope.decls.get(name) {
                 if !hiding.contains(decl_id) {
-                    // Do not hide already hidden decl
+                    // Hide decl only if it's not already hidden
                     last_scope_frame.hiding.insert(*decl_id);
                     return Some(*decl_id);
                 }
@@ -409,8 +409,6 @@ impl<'a> StateWorkingSet<'a> {
     }
 
     pub fn activate_overlay(&mut self, overlay: Vec<(Vec<u8>, DeclId)>) {
-        // TODO: This will overwrite all existing definitions in a scope. When we add deactivate,
-        // we need to re-think how make it recoverable.
         let scope_frame = self
             .delta
             .scope

src/tests.rs

@@ -441,6 +441,46 @@ fn hide_twice_not_allowed() -> TestResult {
     )
 }
 
+#[test]
+fn hides_import_1() -> TestResult {
+    fail_test(
+        r#"module spam { export def foo [] { "foo" } }; use spam; hide spam.foo; foo"#,
+        "not found",
+    )
+}
+
+#[test]
+fn hides_import_2() -> TestResult {
+    fail_test(
+        r#"module spam { export def foo [] { "foo" } }; use spam; hide spam.*; foo"#,
+        "not found",
+    )
+}
+
+#[test]
+fn hides_import_3() -> TestResult {
+    fail_test(
+        r#"module spam { export def foo [] { "foo" } }; use spam; hide spam.[foo]; foo"#,
+        "not found",
+    )
+}
+
+#[test]
+fn hides_import_4() -> TestResult {
+    fail_test(
+        r#"module spam { export def foo [] { "foo" } }; use spam.foo; hide foo; foo"#,
+        "not found",
+    )
+}
+
+#[test]
+fn hides_import_5() -> TestResult {
+    fail_test(
+        r#"module spam { export def foo [] { "foo" } }; use spam.*; hide foo; foo"#,
+        "not found",
+    )
+}
+
 #[test]
 fn def_twice_should_fail() -> TestResult {
     fail_test(
@@ -449,6 +489,15 @@ fn def_twice_should_fail() -> TestResult {
     )
 }
 
+// TODO: This test fails if executed each command on a separate line in REPL
+#[test]
+fn use_import_after_hide() -> TestResult {
+    run_test(
+        r#"module spam { export def foo [] { "foo" } }; use spam.foo; hide foo; use spam.foo; foo"#,
+        "foo",
+    )
+}
+
 #[test]
 fn from_json_1() -> TestResult {
     run_test(r#"('{"name": "Fred"}' | from json).name"#, "Fred")