implement basic set

src/mash/shell/ast/set_definition.py

@@ -24,14 +24,21 @@ def __init__(self, items, condition=None):
         self.condition = condition
 
     def run(self, prev_result='', shell: BaseShell = None, lazy=False):
-        items = [shell.run_commands(item) for item in self.items]
+        items = []
+        for item in self.items.values:
+            results = shell.run_commands(item)
+            for row in results:
+                items.append(row.splitlines())
 
         if lazy:
             return f'{{ {self.items} | {self.condition} }}'
 
-        return list(self.apply(items, shell))
+        result = list(self.apply(items, shell))
+        return ['\n'.join(c) for c in result]
 
     def apply(self, items, shell: BaseShell = None):
+        """Returns the outer product of a nested list.
+        """
         if self.condition is None:
             yield from product(*items)
             return

test/shell/test_parse.py

@@ -569,6 +569,9 @@ def test_parse_set_with_filter():
     assert isinstance(result, SetDefinition)
     result = parse_line('{ users groups | x.id == y.id }')
     assert isinstance(result, SetDefinition)
+    result = parse_line('x <- { users }')
+    assert isinstance(result, Assign)
+    assert isinstance(result.rhs, SetDefinition)
 
     # TODO
     if 0:

test/shell/test_shell_variables.py

@@ -266,3 +266,16 @@ def test_variable_assignment_with_if_then():
 
     run_command('a <- if "" then echo 10', shell=shell)
     assert shell.env['a'] == ''
+
+def test_set_definition():
+    shell = Shell()
+    shell.ignore_invalid_syntax = False
+
+    run_command('a <- range 3', shell=shell)
+    run_command('b <- range 3', shell=shell)
+    run_command('c <- { $a }', shell=shell)
+    assert shell.env['c'] == '0 1 2'
+
+    # TODO
+    run_command('c <- { a b }', shell=shell)
+    run_command('c <- { a b | a == b }', shell=shell)