update website

Summary:
- 4 new issue types
- odoc 2.4 causes some churn but I guess we have to update at some point
  anyway

Reviewed By: geralt-encore

Differential Revision: D57917791

fbshipit-source-id: c187eb6027bb61d97171f421becf28db44d65dda

website/docs/all-issue-types.md

@@ -1243,6 +1243,25 @@ we assume that any captured weak pointer whose name contains "self" is a weak re
 In contrast, `strongSelf` is a local variable to the block, so the check supports any name given to
 a local strong pointer that has been assigned `weakSelf`.
 
+## MUTUAL_RECURSION_CYCLE
+
+Reported as "Mutual Recursion Cycle" by [pulse](/docs/next/checker-pulse).
+
+A recursive call or mutually recursive call has been detected. This does *not* mean that the program won't terminate, just that the code is recursive. You should double-check if the recursion is intended and if it can lead to non-termination or a stack overflow.
+
+Example of recursive function:
+
+
+```C
+int factorial(int x) {
+  if (x > 0) {
+    return x * factorial(x-1);
+  } else {
+    return 1;
+  }
+}
+```
+
 ## NIL_BLOCK_CALL
 
 Reported as "Nil Block Call" by [pulse](/docs/next/checker-pulse).
@@ -1770,6 +1789,48 @@ An example of such variadic methods is
 In this example, if `str` is `nil` then an array `@[@"aaa"]` of size 1 will be
 created, and not an array `@[@"aaa", str, @"bbb"]` of size 3 as expected.
 
+## PULSE_CANNOT_INSTANTIATE_ABSTRACT_CLASS
+
+Reported as "Cannot Instantiate Abstract Class" by [pulse](/docs/next/checker-pulse).
+
+Instantiating an abstract class will lead to `Cannot instantiate abstract class` error.
+
+```hack
+abstract class AbstractClass1 {}
+
+class ConcreteClass1 extends AbstractClass1 {}
+
+public static function makeGeneric<T>(classname<T> $cls): void {
+    new $cls();
+}
+
+<<__ConsistentConstruct>>
+abstract class AbstractClass2 {
+
+  public static function makeStatic(): void {
+    new static();
+  }
+}
+
+class ConcreteClass2 extends AbstractClass2 {}
+
+public function badViaGeneric(): void {
+    Main::makeGeneric(AbstractClass1::class); // ERROR!
+}
+
+public function goodViaGeneric(): void {
+  Main::makeGeneric(ConcreteClass1::class);
+}
+
+public function badViaStatic(): void {
+  AbstractClass2::makeStatic(); // ERROR!
+}
+
+public function goodViaStatic(): void {
+  ConcreteClass2::makeStatic();
+}
+```
+
 ## PULSE_CONST_REFABLE
 
 Reported as "Const Refable Parameter" by [pulse](/docs/next/checker-pulse).
@@ -1806,6 +1867,16 @@ function simple_bad() : int {
 }
 ```
 
+## PULSE_DYNAMIC_TYPE_MISMATCH
+
+Reported as "Dynamic Type Mismatch" by [pulse](/docs/next/checker-pulse).
+
+This error is reported in Hack. It fires when we detect an operation that is incompatible
+with the dynamic type of its arguments.
+
+For example, reading `$x['key']` when `$x` is a vector.
+
+
 ## PULSE_READONLY_SHARED_PTR_PARAM
 
 Reported as "Read-only Shared Parameter" by [pulse](/docs/next/checker-pulse).
@@ -2486,6 +2557,41 @@ hierarchy:
 @end
 ```
 
+## RETAIN_CYCLE_NO_WEAK_INFO
+
+Reported as "Retain Cycle No Weak Info" by [pulse](/docs/next/checker-pulse).
+
+A retain cycle is a situation when object A retains object B, and object B
+retains object A at the same time. Here is an example:
+
+```objectivec
+@class Child;
+@interface Parent : NSObject {
+    Child *child; // Instance variables are implicitly __strong
+}
+@end
+@interface Child : NSObject {
+    Parent *parent;
+}
+@end
+```
+
+You can fix a retain cycle in ARC by using \_\_weak variables or weak properties
+for your "back links", i.e. links to direct or indirect parents in an object
+hierarchy:
+
+```objectivec
+@class Child;
+@interface Parent : NSObject {
+    Child *child;
+}
+@end
+@interface Child : NSObject {
+    __weak Parent *parent;
+}
+@end
+```
+
 ## SCOPE_LEAKAGE
 
 Reported as "Scope Leakage" by [scope-leakage](/docs/next/checker-scope-leakage).

website/docs/checker-pulse.md

@@ -151,6 +151,7 @@ The following issue types are reported by this checker:
 - [DATA_FLOW_TO_SINK](/docs/next/all-issue-types#data_flow_to_sink)
 - [MEMORY_LEAK_C](/docs/next/all-issue-types#memory_leak_c)
 - [MEMORY_LEAK_CPP](/docs/next/all-issue-types#memory_leak_cpp)
+- [MUTUAL_RECURSION_CYCLE](/docs/next/all-issue-types#mutual_recursion_cycle)
 - [NIL_BLOCK_CALL](/docs/next/all-issue-types#nil_block_call)
 - [NIL_BLOCK_CALL_LATENT](/docs/next/all-issue-types#nil_block_call_latent)
 - [NIL_INSERTION_INTO_COLLECTION](/docs/next/all-issue-types#nil_insertion_into_collection)
@@ -175,8 +176,10 @@ The following issue types are reported by this checker:
 - [NULL_ARGUMENT_LATENT](/docs/next/all-issue-types#null_argument_latent)
 - [OPTIONAL_EMPTY_ACCESS](/docs/next/all-issue-types#optional_empty_access)
 - [OPTIONAL_EMPTY_ACCESS_LATENT](/docs/next/all-issue-types#optional_empty_access_latent)
+- [PULSE_CANNOT_INSTANTIATE_ABSTRACT_CLASS](/docs/next/all-issue-types#pulse_cannot_instantiate_abstract_class)
 - [PULSE_CONST_REFABLE](/docs/next/all-issue-types#pulse_const_refable)
 - [PULSE_DICT_MISSING_KEY](/docs/next/all-issue-types#pulse_dict_missing_key)
+- [PULSE_DYNAMIC_TYPE_MISMATCH](/docs/next/all-issue-types#pulse_dynamic_type_mismatch)
 - [PULSE_READONLY_SHARED_PTR_PARAM](/docs/next/all-issue-types#pulse_readonly_shared_ptr_param)
 - [PULSE_REFERENCE_STABILITY](/docs/next/all-issue-types#pulse_reference_stability)
 - [PULSE_RESOURCE_LEAK](/docs/next/all-issue-types#pulse_resource_leak)
@@ -195,6 +198,7 @@ The following issue types are reported by this checker:
 - [PULSE_UNNECESSARY_COPY_OPTIONAL_CONST](/docs/next/all-issue-types#pulse_unnecessary_copy_optional_const)
 - [PULSE_UNNECESSARY_COPY_RETURN](/docs/next/all-issue-types#pulse_unnecessary_copy_return)
 - [RETAIN_CYCLE](/docs/next/all-issue-types#retain_cycle)
+- [RETAIN_CYCLE_NO_WEAK_INFO](/docs/next/all-issue-types#retain_cycle_no_weak_info)
 - [SENSITIVE_DATA_FLOW](/docs/next/all-issue-types#sensitive_data_flow)
 - [STACK_VARIABLE_ADDRESS_ESCAPE](/docs/next/all-issue-types#stack_variable_address_escape)
 - [TAINT_ERROR](/docs/next/all-issue-types#taint_error)