11
Profanity
Copyright (C) 2012 - 2015 James Booth <boothj5@gmail.com>

Profanity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Profanity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Profanity.  If not, see <http://www.gnu.org/licenses/>.

There is an additional exception from the author permitting linking
with OpenSSL:

As copyright holder, I give permission for profanity to be linked to
the OpenSSL libraries. This includes permission for profanity
binaries to be distributed linked against the OpenSSL libraries.
All other obligations under the GPL v3 remain intact.

//:: Container definitions can contain 'type ingredients'

//: pre-requisite: extend our notion of containers to not necessarily be
//: atomic types
:(after "Update GET base_type in Check")
base_type = get_base_type(base_type);
:(after "Update GET base_type in Run")
base_type = get_base_type(base_type);
:(after "Update PUT base_type in Check")
base_type = get_base_type(base_type);
:(after "Update PUT base_type in Run")
base_type = get_base_type(base_type);
:(after "Update MAYBE_CONVERT base_type in Check")
base_type = get_base_type(base_type);
:(after "Update base_type in element_type")
base_type = get_base_type(base_type);
:(after "Update base_type in skip_addresses")
base_type = get_base_type(base_type);
:(replace{} "const type_tree* get_base_type(const type_tree* t)")
const type_tree* get_base_type(const type_tree* t) {
  const type_tree* result = t->atom ? t : t->left;
  if (!result->atom)
    raise << "invalid type " << to_string(t) << '\n' << end();
  return result;
}

:(scenario ill_formed_container)
% Hide_errors = true;
def main [
  {1: ((foo) num)} <- copy 0
]
# no crash

//: update size_of to handle non-atom container types

:(scenario size_of_shape_shifting_container)
container foo:_t [
  x:_t
  y:num
]
def main [
  1:foo:num <- merge 12, 13
  3:foo:point <- merge 14, 15, 16
]
+mem: storing 12 in location 1
+mem: storing 13 in location 2
+mem: storing 14 in location 3
+mem: storing 15 in location 4
+mem: storing 16 in location 5

:(scenario size_of_shape_shifting_container_2)
# multiple type ingredients
container foo:_a:_b [
  x:_a
  y:_b
]
def main [
  1:foo:num:bool <- merge 34, true
]
$error: 0

:(scenario size_of_shape_shifting_container_3)
container foo:_a:_b [
  x:_a
  y:_b
]
def main [
  1:text <- new [abc]
  # compound types for type ingredients
  {3: (foo number (address array character))} <- merge 34/x, 1:text/y
]
$error: 0

:(scenario size_of_shape_shifting_container_4)
container foo:_a:_b [
  x:_a
  y:_b
]
container bar:_a:_b [
  # dilated element
  {data: (foo _a (address _b))}
]
def main [
  1:text <- new [abc]
  3:bar:num:@:char <- merge 34/x, 1:text/y
]
$error: 0

:(scenario shape_shifting_container_extend)
container foo:_a [
  x:_a
]
container foo:_a [
  y:_a
]
$error: 0

:(scenario shape_shifting_container_extend_error)
% Hide_errors = true;
container foo:_a [
  x:_a
]
container foo:_b [
  y:_b
]
+error: headers of container 'foo' must use identical type ingredients

:(scenario type_ingredient_must_start_with_underscore)
% Hide_errors = true;
container foo:t [
  x:num
]
+error: foo: type ingredient 't' must begin with an underscore

:(before "End Globals")
// We'll use large type ordinals to mean "the following type of the variable".
// For example, if we have a generic type called foo:_elem, the type
// ingredient _elem in foo's type_info will have value START_TYPE_INGREDIENTS,
// and we'll handle it by looking in the current reagent for the next type
// that appears after foo.
extern const int START_TYPE_INGREDIENTS = 2000;
:(before "End Commandline Parsing")  // after loading .mu files
assert(Next_type_ordinal < START_TYPE_INGREDIENTS);

:(before "End type_info Fields")
map<string, type_ordinal> type_ingredient_names;

//: Suppress unknown type checks in shape-shifting containers.

:(before "Check Container Field Types(info)")
if (!info.type_ingredient_names.empty()) continue;

:(before "End container Name Refinements")
if (name.find(':') != string::npos) {
  trace("parse") << "container has type ingredients; parsing" << end();
  if (!read_type_ingredients(name, command)) {
    // error; skip rest of the container definition and continue
    slurp_balanced_bracket(in);
    return;
  }
}

:(code)
bool read_type_ingredients(string& name, const string& command) {
  string save_name = name;
  istringstream in(save_name);
  name = slurp_until(in, ':');
  map<string, type_ordinal> type_ingredient_names;
  if (!slurp_type_ingredients(in, type_ingredient_names, name)) {
    return false;
  }
  if (contains_key(Type_ordinal, name)
      && contains_key(Type, get(Type_ordinal, name))) {
    const type_info& previous_info = get(Type, get(Type_ordinal, name));
    // we've already seen this container; make sure type ingredients match
    if (!type_ingredients_match(type_ingredient_names, previous_info.type_ingredient_names)) {
      raise << "headers of " << command << " '" << name << "' must use identical type ingredients\n" << end();
      return false;
    }
    return true;
  }
  // we haven't seen this container before
  if (!contains_key(Type_ordinal, name) || get(Type_ordinal, name) == 0)
    put(Type_ordinal, name, Next_type_ordinal++);
  type_info& info = get_or_insert(Type, get(Type_ordinal, name));
  info.type_ingredient_names.swap(type_ingredient_names);
  return true;
}

bool slurp_type_ingredients(istream& in, map<string, type_ordinal>& out, const string& container_name) {
  int next_type_ordinal = START_TYPE_INGREDIENTS;
  while (has_data(in)) {
    string curr = slurp_until(in, ':');
    if (curr.empty()) {
      raise << container_name << ": empty type ingredients not permitted\n" << end();
      return false;
    }
    if (!starts_with(curr, "_")) {
      raise << container_name << ": type ingredient '" << curr << "' must begin with an underscore\n" << end();
      return false;
    }
    if (out.find(curr) != out.end()) {
      raise << container_name << ": can't repeat type ingredient name'" << curr << "' in a single container definition\n" << end();
      return false;
    }
    put(out, curr, next_type_ordinal++);
  }
  return true;
}

bool type_ingredients_match(const map<string, type_ordinal>& a, const map<string, type_ordinal>& b) {
  if (SIZE(a) != SIZE(b)) return false;
  for (map<string, type_ordinal>::const_iterator p = a.begin();  p != a.end();  ++p) {
    if (!contains_key(b, p->first)) return false;
    if (p->second != get(b, p->first)) return false;
  }
  return true;
}

:(before "End insert_container Special-cases")
// check for use of type ingredients
else if (is_type_ingredient_name(type->name)) {
  type->value = get(info.type_ingredient_names, type->name);
}
:(code)
bool is_type_ingredient_name(const string& type) {
  return starts_with(type, "_");
}

:(before "End Container Type Checks")
if (type->value >= START_TYPE_INGREDIENTS
    && (type->value - START_TYPE_INGREDIENTS) < SIZE(get(Type, type->value).type_ingredient_names))
  return;

:(scenario size_of_shape_shifting_exclusive_container)
exclusive-container foo:_t [
  x:_t
  y:num
]
def main [
  1:foo:num <- merge 0/x, 34
  3:foo:point <- merge 0/x, 15, 16
  6:foo:point <- merge 1/y, 23
]
+run: {1: ("foo" "number")} <- merge {0: "literal", "x": ()}, {34: "literal"}
+mem: storing 0 in location 1
+mem: storing 34 in location 2
+run: {3: ("foo" "point")} <- merge {0: "literal", "x": ()}, {15: "literal"}, {16: "literal"}
+mem: storing 0 in location 3
+mem: storing 15 in location 4
+mem: storing 16 in location 5
+run: {6: ("foo" "point")} <- merge {1: "literal", "y": ()}, {23: "literal"}
+mem: storing 1 in location 6
+mem: storing 23 in location 7
+run: return
# no other stores
% CHECK_EQ(trace_count_prefix("mem", "storing"), 7);

:(before "End variant_type Special-cases")
if (contains_type_ingredient(element))
  replace_type_ingredients(element.type, type->right, info, " while computing variant type of exclusive-container");

:(scenario get_on_shape_shifting_container)
container foo:_t [
  x:_t
  y:num
]
def main [
  1:foo:point <- merge 14, 15, 16
  4:num <- get 1:foo:point, y:offset
]
+mem: storing 16 in location 4

:(scenario get_on_shape_shifting_container_2)
container foo:_t [
  x:_t
  y:num
]
def main [
  1:foo:point <- merge 14, 15, 16
  4:point <- get 1:foo:point, x:offset
]
+mem: storing 14 in location 4
+mem: storing 15 in location 5

:(scenario get_on_shape_shifting_container_3)
container foo:_t [
  x:_t
  y:num
]
def main [
  1:num/alloc-id, 2:num <- copy 0, 34
  3:foo:&:point <- merge 1:&:point, 48
  6:&:point <- get 1:foo:&:point, x:offset
]
+mem: storing 0 in location 6
+mem: storing 34 in location 7

:(scenario get_on_shape_shifting_container_inside_container)
container foo:_t [
  x:_t
  y:num
]
container bar [
  x:foo:point
  y:num
]
def main [
  1:bar <- merge 14, 15, 16, 17
  5:num <- get 1:bar, 1:offset
]
+mem: storing 17 in location 5

:(scenario get_on_complex_shape_shifting_container)
container foo:_a:_b [
  x:_a
  y:_b
]
def main [
  1:text <- new [abc]
  {3: (foo number (address array character))} <- merge 34/x, 1:text/y
  6:text <- get {3: (foo number (address array character))}, y:offset
  8:bool <- equal 1:text, 6:text
]
+mem: storing 1 in location 8

:(before "End element_type Special-cases")
replace_type_ingredients(element, type, info, " while computing element type of container");

:(before "End size_of(type) Non-atom Special-cases")
assert(type->left->atom);
if (!contains_key(Type, type->left->value)) {
  raise << "no such type " << type->left->value << '\n' << end();
  return 0;
}
type_info t = get(Type, type->left->value);
if (t.kind == CONTAINER) {
  // size of a container is the sum of the sizes of its elements
  int result = 0;
  for (int i = 0; i < SIZE(t.elements); ++i) {
    // todo: strengthen assertion to disallow mutual type recursion
    if (get_base_type(t.elements.at(i).type)->value == get_base_type(type)->value) {
      raise << "container " << t.name << " can't include itself as a member\n" << end();
      return 0;
    }
    result += size_of(element_type(type, i));
  }
  return result;
}
if (t.kind == EXCLUSIVE_CONTAINER) {
  // size of an exclusive container is the size of its largest variant
  // (So like containers, it can't contain arrays.)
  int result = 0;
  for (int i = 0; i < SIZE(t.elements); ++i) {
    reagent tmp;
    tmp.type = new type_tree(*type);
    int size = size_of(variant_type(tmp, i));
    if (size > result) result = size;
  }
  // ...+1 for its tag.
  return result+1;
}

:(scenario complex_shape_shifting_exclusive_container)
exclusive-container foo:_a [
  x:_a
  y:num
]
def main [
  1:text <- new [abc]
  3:foo:point <- merge 0/variant, 34/xx, 35/xy
  10:point, 20:bool <- maybe-convert 3:foo:point, 0/variant
]
+mem: storing 1 in location 20
+mem: storing 35 in location 11

:(code)
bool contains_type_ingredient(const reagent& x) {
  return contains_type_ingredient(x.type);
}

bool contains_type_ingredient(const type_tree* type) {
  if (!type) return false;
  if (type->atom) return type->value >= START_TYPE_INGREDIENTS;
  return contains_type_ingredient(type->left) || contains_type_ingredient(type->right);
}

void replace_type_ingredients(reagent& element, const type_tree* caller_type, const type_info& info, const string& location_for_error_messages) {
  if (contains_type_ingredient(element)) {
    if (!caller_type->right)
      raise << "illegal type " << names_to_string(caller_type) << " seems to be missing a type ingredient or three" << location_for_error_messages << '\n' << end();
    replace_type_ingredients(element.type, caller_type->right, info, location_for_error_messages);
  }
}

// replace all type_ingredients in element_type with corresponding elements of callsite_type
void replace_type_ingredients(type_tree* element_type, const type_tree* callsite_type, const type_info& container_info, const string& location_for_error_messages) {
  if (!callsite_type) return;  // error but it's already been raised above
  if (!element_type) return;
  if (!element_type->atom) {
    if (element_type->right == NULL && is_type_ingredient(element_type->left)) {
      int type_ingredient_index = to_type_ingredient_index(element_type->left);
      if (corresponding(callsite_type, type_ingredient_index, is_final_type_ingredient(type_ingredient_index, container_info))->right) {
        // replacing type ingredient at end of list, and replacement is a non-degenerate compound type -- (a b) but not (a)
        replace_type_ingredient_at(type_ingredient_index, element_type, callsite_type, container_info, location_for_error_messages);
        return;
      }
    }
    replace_type_ingredients(element_type->left, callsite_type, container_info, location_for_error_messages);
    replace_type_ingredients(element_type->right, callsite_type, container_info, location_for_error_messages);
    return;
  }
  if (is_type_ingredient(element_type))
    replace_type_ingredient_at(to_type_ingredient_index(element_type), element_type, callsite_type, container_info, location_for_error_messages);
}

const type_tree* corresponding(const type_tree* type, int index, bool final) {
  for (const type_tree* curr = type;  curr;  curr = curr->right, --index) {
    assert_for_now(!curr->atom);
    if (index == 0)
      return final ? curr : curr->left;
  }
  assert_for_now(false);
}

bool is_type_ingredient(const type_tree* type) {
  return type->atom && type->value >= START_TYPE_INGREDIENTS;
}

int to_type_ingredient_index(const type_tree* type) {
  assert(type->atom);
  return type->value-START_TYPE_INGREDIENTS;
}

void replace_type_ingredient_at(const int type_ingredient_index, type_tree* element_type, const type_tree* callsite_type, const type_info& container_info, const string& location_for_error_messages) {
  if (!has_nth_type(callsite_type, type_ingredient_index)) {
    raise << "illegal type " << names_to_string(callsite_type) << " seems to be missing a type ingredient or three" << location_for_error_messages << '\n' << end();
    return;
  }
  *element_type = *nth_type_ingredient(callsite_type, type_ingredient_index, container_info);
}

const type_tree* nth_type_ingredient(const type_tree* callsite_type, int type_ingredient_index, const type_info& container_info) {
  bool final = is_final_type_ingredient(type_ingredient_index, container_info);
  const type_tree* curr = callsite_type;
  for (int i = 0;  i < type_ingredient_index;  ++i) {
    assert(curr);
    assert(!curr->atom);
//?     cerr << "type ingredient " << i << " is " << to_string(curr->left) << '\n';
    curr = curr->right;
  }
  assert(curr);
  if (curr->atom) return curr;
  if (!final) return curr->left;
  if (!curr->right) return curr->left;
  return curr;
}

bool is_final_type_ingredient(int type_ingredient_index, const type_info& container_info) {
  for (map<string, type_ordinal>::const_iterator p = container_info.type_ingredient_names.begin();
       p != container_info.type_ingredient_names.end();
       ++p) {
    if (p->second > START_TYPE_INGREDIENTS+type_ingredient_index) return false;
  }
  return true;
}

:(before "End Unit Tests")
void test_replace_type_ingredients_entire() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "  y:num\n"
      "]\n");
  reagent callsite("x:foo:point");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: \"point\"}");
}

void test_replace_type_ingredients_tail() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "]\n"
      "container bar:_elem [\n"
      "  x:foo:_elem\n"
      "]\n");
  reagent callsite("x:bar:point");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: (\"foo\" \"point\")}");
}

void test_replace_type_ingredients_head_tail_multiple() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "]\n"
      "container bar:_elem [\n"
      "  x:foo:_elem\n"
      "]\n");
  reagent callsite("x:bar:address:array:character");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: (\"foo\" \"address\" \"array\" \"character\")}");
}

void test_replace_type_ingredients_head_middle() {
  run("container foo:_elem [\n"
      "  x:_elem\n"
      "]\n"
      "container bar:_elem [\n"
      "  x:foo:_elem:num\n"
      "]\n");
  reagent callsite("x:bar:address");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{x: (\"foo\" \"address\" \"number\")}");
}

void test_replace_last_type_ingredient_with_multiple() {
  run("container foo:_a:_b [\n"
      "  x:_a\n"
      "  y:_b\n"
      "]\n");
  reagent callsite("{f: (foo number (address array character))}");
  reagent element1 = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element1), "{x: \"number\"}");
  reagent element2 = element_type(callsite.type, 1);
  CHECK_EQ(to_string(element2), "{y: (\"address\" \"array\" \"character\")}");
}

void test_replace_last_type_ingredient_inside_compound() {
  run("container foo:_a:_b [\n"
      "  {x: (bar _a (address _b))}\n"
      "]\n");
  reagent callsite("f:foo:number:array:character");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(names_to_string_without_quotes(element.type), "(bar number (address array character))");
}

void test_replace_middle_type_ingredient_with_multiple() {
  run("container foo:_a:_b:_c [\n"
      "  x:_a\n"
      "  y:_b\n"
      "  z:_c\n"
      "]\n");
  reagent callsite("{f: (foo number (address array character) boolean)}");
  reagent element1 = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element1), "{x: \"number\"}");
  reagent element2 = element_type(callsite.type, 1);
  CHECK_EQ(to_string(element2), "{y: (\"address\" \"array\" \"character\")}");
  reagent element3 = element_type(callsite.type, 2);
  CHECK_EQ(to_string(element3), "{z: \"boolean\"}");
}

void test_replace_middle_type_ingredient_with_multiple2() {
  run("container foo:_key:_value [\n"
      "  key:_key\n"
      "  value:_value\n"
      "]\n");
  reagent callsite("{f: (foo (address array character) number)}");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{key: (\"address\" \"array\" \"character\")}");
}

void test_replace_middle_type_ingredient_with_multiple3() {
  run("container foo_table:_key:_value [\n"
      "  data:&:@:foo_table_row:_key:_value\n"
      "]\n"
      "\n"
      "container foo_table_row:_key:_value [\n"
      "  key:_key\n"
      "  value:_value\n"
      "]\n");
  reagent callsite("{f: (foo_table (address array character) number)}");
  reagent element = element_type(callsite.type, 0);
  CHECK_EQ(to_string(element), "{data: (\"address\" \"array\" \"foo_table_row\" (\"address\" \"array\" \"character\") \"number\")}");
}

:(code)
bool has_nth_type(const type_tree* base, int n) {
  assert(n >= 0);
  if (!base) return false;
  if (n == 0) return true;
  return has_nth_type(base->right, n-1);
}

:(scenario get_on_shape_shifting_container_error)
% Hide_errors = true;
container foo:_t [
  x:_t
  y:num
]
def main [
  1:foo:point <- merge 14, 15, 16
  10:num <- get 1:foo, 1:offset
]
# todo: improve error message
+error: illegal type "foo" seems to be missing a type ingredient or three while computing element type of container

:(scenario typos_in_container_definitions)
% Hide_errors = true;
container foo:_t [
  x:adress:_t  # typo
]
def main [
  local-scope
  x:address:foo:num <- new {(foo num): type}
]
# no crash

:(scenario typos_in_recipes)
% Hide_errors = true;
def foo [
  local-scope
  x:adress:array:number <- copy null  # typo
]
# shouldn't crash

//:: 'merge' on shape-shifting containers

:(scenario merge_check_shape_shifting_container_containing_exclusive_container)
container foo:_elem [
  x:num
  y:_elem
]
exclusive-container bar [
  x:num
  y:num
]
def main [
  1:foo:bar <- merge 23, 1/y, 34
]
+mem: storing 23 in location 1
+mem: storing 1 in location 2
+mem: storing 34 in location 3
$error: 0

:(scenario merge_check_shape_shifting_container_containing_exclusive_container_2)
% Hide_errors = true;
container foo:_elem [
  x:num
  y:_elem
]
exclusive-container bar [
  x:num
  y:num
]
def main [
  1:foo:bar <- merge 23, 1/y, 34, 35
]
+error: main: too many ingredients in '1:foo:bar <- merge 23, 1/y, 34, 35'

:(scenario merge_check_shape_shifting_exclusive_container_containing_container)
exclusive-container foo:_elem [
  x:num
  y:_elem
]
container bar [
  x:num
  y:num
]
def main [
  1:foo:bar <- merge 1/y, 23, 34
]
+mem: storing 1 in location 1
+mem: storing 23 in location 2
+mem: storing 34 in location 3
$error: 0

:(scenario merge_check_shape_shifting_exclusive_container_containing_container_2)
exclusive-container foo:_elem [
  x:num
  y:_elem
]
container bar [
  x:num
  y:num
]
def main [
  1:foo:bar <- merge 0/x, 23
]
$error: 0

:(scenario merge_check_shape_shifting_exclusive_container_containing_container_3)
% Hide_errors = true;
exclusive-container foo:_elem [
  x:num
  y:_elem
]
container bar [
  x:num
  y:num
]
def main [
  1:foo:bar <- merge 1/y, 23
]
+error: main: too few ingredients in '1:foo:bar <- merge 1/y, 23'