Add a script to check the public API

We would like to check for API changes during development and in CI so
that such changes can be discussed separately from the code.

Add tooling and documentation for creating API listings for the public
crates within the workspace (i.e., not `internals`).

Add API text files from an initial run of the script.

CONTRIBUTING.md

@@ -226,6 +226,11 @@ Use of `unsafe` code is prohibited unless there is a unanimous decision among
 library maintainers on the exclusion from this rule. In such cases there is a
 requirement to test unsafe code with sanitizers including Miri.
 
+### API changes
+
+All PRs that change the public API of `rust-bitcoin` must include a patch to
+the `api/` text files. This should be a separate, final patch to the PR
+that is the diff created by running `./contrib/check-for-api-changes.sh`.
 
 ### Policy
 

api/README.md

@@ -0,0 +1,12 @@
+# API text files
+
+Each file here lists the public API when built with some set of features
+enabled. To create these files run `../contrib/check-for-api-changes.sh`:
+
+Requires `cargo-public-api`, install with:
+
+```
+cargo +stable install cargo-public-api --locked
+```
+
+ref: https://github.com/enselic/cargo-public-api

api/base58/default-features.txt

@@ -0,0 +1,100 @@
+#[non_exhaustive] pub enum base58ck::Error
+#[non_exhaustive] pub enum base58ck::error::Error
+impl base58ck::error::IncorrectChecksumError
+impl base58ck::error::InvalidCharacterError
+impl base58ck::error::TooShortError
+impl core::clone::Clone for base58ck::error::Error
+impl core::clone::Clone for base58ck::error::IncorrectChecksumError
+impl core::clone::Clone for base58ck::error::InvalidCharacterError
+impl core::clone::Clone for base58ck::error::TooShortError
+impl core::cmp::Eq for base58ck::error::Error
+impl core::cmp::Eq for base58ck::error::IncorrectChecksumError
+impl core::cmp::Eq for base58ck::error::InvalidCharacterError
+impl core::cmp::Eq for base58ck::error::TooShortError
+impl core::cmp::PartialEq for base58ck::error::Error
+impl core::cmp::PartialEq for base58ck::error::IncorrectChecksumError
+impl core::cmp::PartialEq for base58ck::error::InvalidCharacterError
+impl core::cmp::PartialEq for base58ck::error::TooShortError
+impl core::convert::From<base58ck::error::IncorrectChecksumError> for base58ck::error::Error
+impl core::convert::From<base58ck::error::InvalidCharacterError> for base58ck::error::Error
+impl core::convert::From<base58ck::error::TooShortError> for base58ck::error::Error
+impl core::convert::From<core::convert::Infallible> for base58ck::error::Error
+impl core::error::Error for base58ck::error::Error
+impl core::error::Error for base58ck::error::IncorrectChecksumError
+impl core::error::Error for base58ck::error::InvalidCharacterError
+impl core::error::Error for base58ck::error::TooShortError
+impl core::fmt::Debug for base58ck::error::Error
+impl core::fmt::Debug for base58ck::error::IncorrectChecksumError
+impl core::fmt::Debug for base58ck::error::InvalidCharacterError
+impl core::fmt::Debug for base58ck::error::TooShortError
+impl core::fmt::Display for base58ck::error::Error
+impl core::fmt::Display for base58ck::error::IncorrectChecksumError
+impl core::fmt::Display for base58ck::error::InvalidCharacterError
+impl core::fmt::Display for base58ck::error::TooShortError
+impl core::marker::Freeze for base58ck::error::Error
+impl core::marker::Freeze for base58ck::error::IncorrectChecksumError
+impl core::marker::Freeze for base58ck::error::InvalidCharacterError
+impl core::marker::Freeze for base58ck::error::TooShortError
+impl core::marker::Send for base58ck::error::Error
+impl core::marker::Send for base58ck::error::IncorrectChecksumError
+impl core::marker::Send for base58ck::error::InvalidCharacterError
+impl core::marker::Send for base58ck::error::TooShortError
+impl core::marker::StructuralPartialEq for base58ck::error::Error
+impl core::marker::StructuralPartialEq for base58ck::error::IncorrectChecksumError
+impl core::marker::StructuralPartialEq for base58ck::error::InvalidCharacterError
+impl core::marker::StructuralPartialEq for base58ck::error::TooShortError
+impl core::marker::Sync for base58ck::error::Error
+impl core::marker::Sync for base58ck::error::IncorrectChecksumError
+impl core::marker::Sync for base58ck::error::InvalidCharacterError
+impl core::marker::Sync for base58ck::error::TooShortError
+impl core::marker::Unpin for base58ck::error::Error
+impl core::marker::Unpin for base58ck::error::IncorrectChecksumError
+impl core::marker::Unpin for base58ck::error::InvalidCharacterError
+impl core::marker::Unpin for base58ck::error::TooShortError
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::Error
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::IncorrectChecksumError
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::InvalidCharacterError
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::TooShortError
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::Error
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::IncorrectChecksumError
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::InvalidCharacterError
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::TooShortError
+pub base58ck::Error::Decode(base58ck::error::InvalidCharacterError)
+pub base58ck::Error::IncorrectChecksum(base58ck::error::IncorrectChecksumError)
+pub base58ck::Error::TooShort(base58ck::error::TooShortError)
+pub base58ck::error::Error::Decode(base58ck::error::InvalidCharacterError)
+pub base58ck::error::Error::IncorrectChecksum(base58ck::error::IncorrectChecksumError)
+pub base58ck::error::Error::TooShort(base58ck::error::TooShortError)
+pub fn base58ck::decode(data: &str) -> core::result::Result<alloc::vec::Vec<u8>, base58ck::error::InvalidCharacterError>
+pub fn base58ck::decode_check(data: &str) -> core::result::Result<alloc::vec::Vec<u8>, base58ck::error::Error>
+pub fn base58ck::encode(data: &[u8]) -> alloc::string::String
+pub fn base58ck::encode_check(data: &[u8]) -> alloc::string::String
+pub fn base58ck::encode_check_to_fmt(fmt: &mut core::fmt::Formatter<'_>, data: &[u8]) -> core::fmt::Result
+pub fn base58ck::error::Error::clone(&self) -> base58ck::error::Error
+pub fn base58ck::error::Error::eq(&self, other: &base58ck::error::Error) -> bool
+pub fn base58ck::error::Error::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::Error::from(e: base58ck::error::IncorrectChecksumError) -> Self
+pub fn base58ck::error::Error::from(e: base58ck::error::InvalidCharacterError) -> Self
+pub fn base58ck::error::Error::from(e: base58ck::error::TooShortError) -> Self
+pub fn base58ck::error::Error::from(never: core::convert::Infallible) -> Self
+pub fn base58ck::error::Error::source(&self) -> core::option::Option<&(dyn core::error::Error + 'static)>
+pub fn base58ck::error::IncorrectChecksumError::clone(&self) -> base58ck::error::IncorrectChecksumError
+pub fn base58ck::error::IncorrectChecksumError::eq(&self, other: &base58ck::error::IncorrectChecksumError) -> bool
+pub fn base58ck::error::IncorrectChecksumError::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::IncorrectChecksumError::incorrect_checksum(&self) -> (u32, u32)
+pub fn base58ck::error::InvalidCharacterError::clone(&self) -> base58ck::error::InvalidCharacterError
+pub fn base58ck::error::InvalidCharacterError::eq(&self, other: &base58ck::error::InvalidCharacterError) -> bool
+pub fn base58ck::error::InvalidCharacterError::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::InvalidCharacterError::invalid_base58_character(&self) -> u8
+pub fn base58ck::error::TooShortError::clone(&self) -> base58ck::error::TooShortError
+pub fn base58ck::error::TooShortError::eq(&self, other: &base58ck::error::TooShortError) -> bool
+pub fn base58ck::error::TooShortError::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::TooShortError::invalid_base58_length(&self) -> usize
+pub mod base58ck
+pub mod base58ck::error
+pub struct base58ck::InvalidCharacterError
+pub struct base58ck::error::IncorrectChecksumError
+pub struct base58ck::error::InvalidCharacterError
+pub struct base58ck::error::TooShortError
+pub use base58ck::String
+pub use base58ck::Vec

api/base58/no-features.txt

@@ -0,0 +1,95 @@
+#[non_exhaustive] pub enum base58ck::Error
+#[non_exhaustive] pub enum base58ck::error::Error
+impl base58ck::error::IncorrectChecksumError
+impl base58ck::error::InvalidCharacterError
+impl base58ck::error::TooShortError
+impl core::clone::Clone for base58ck::error::Error
+impl core::clone::Clone for base58ck::error::IncorrectChecksumError
+impl core::clone::Clone for base58ck::error::InvalidCharacterError
+impl core::clone::Clone for base58ck::error::TooShortError
+impl core::cmp::Eq for base58ck::error::Error
+impl core::cmp::Eq for base58ck::error::IncorrectChecksumError
+impl core::cmp::Eq for base58ck::error::InvalidCharacterError
+impl core::cmp::Eq for base58ck::error::TooShortError
+impl core::cmp::PartialEq for base58ck::error::Error
+impl core::cmp::PartialEq for base58ck::error::IncorrectChecksumError
+impl core::cmp::PartialEq for base58ck::error::InvalidCharacterError
+impl core::cmp::PartialEq for base58ck::error::TooShortError
+impl core::convert::From<base58ck::error::IncorrectChecksumError> for base58ck::error::Error
+impl core::convert::From<base58ck::error::InvalidCharacterError> for base58ck::error::Error
+impl core::convert::From<base58ck::error::TooShortError> for base58ck::error::Error
+impl core::convert::From<core::convert::Infallible> for base58ck::error::Error
+impl core::fmt::Debug for base58ck::error::Error
+impl core::fmt::Debug for base58ck::error::IncorrectChecksumError
+impl core::fmt::Debug for base58ck::error::InvalidCharacterError
+impl core::fmt::Debug for base58ck::error::TooShortError
+impl core::fmt::Display for base58ck::error::Error
+impl core::fmt::Display for base58ck::error::IncorrectChecksumError
+impl core::fmt::Display for base58ck::error::InvalidCharacterError
+impl core::fmt::Display for base58ck::error::TooShortError
+impl core::marker::Freeze for base58ck::error::Error
+impl core::marker::Freeze for base58ck::error::IncorrectChecksumError
+impl core::marker::Freeze for base58ck::error::InvalidCharacterError
+impl core::marker::Freeze for base58ck::error::TooShortError
+impl core::marker::Send for base58ck::error::Error
+impl core::marker::Send for base58ck::error::IncorrectChecksumError
+impl core::marker::Send for base58ck::error::InvalidCharacterError
+impl core::marker::Send for base58ck::error::TooShortError
+impl core::marker::StructuralPartialEq for base58ck::error::Error
+impl core::marker::StructuralPartialEq for base58ck::error::IncorrectChecksumError
+impl core::marker::StructuralPartialEq for base58ck::error::InvalidCharacterError
+impl core::marker::StructuralPartialEq for base58ck::error::TooShortError
+impl core::marker::Sync for base58ck::error::Error
+impl core::marker::Sync for base58ck::error::IncorrectChecksumError
+impl core::marker::Sync for base58ck::error::InvalidCharacterError
+impl core::marker::Sync for base58ck::error::TooShortError
+impl core::marker::Unpin for base58ck::error::Error
+impl core::marker::Unpin for base58ck::error::IncorrectChecksumError
+impl core::marker::Unpin for base58ck::error::InvalidCharacterError
+impl core::marker::Unpin for base58ck::error::TooShortError
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::Error
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::IncorrectChecksumError
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::InvalidCharacterError
+impl core::panic::unwind_safe::RefUnwindSafe for base58ck::error::TooShortError
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::Error
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::IncorrectChecksumError
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::InvalidCharacterError
+impl core::panic::unwind_safe::UnwindSafe for base58ck::error::TooShortError
+pub base58ck::Error::Decode(base58ck::error::InvalidCharacterError)
+pub base58ck::Error::IncorrectChecksum(base58ck::error::IncorrectChecksumError)
+pub base58ck::Error::TooShort(base58ck::error::TooShortError)
+pub base58ck::error::Error::Decode(base58ck::error::InvalidCharacterError)
+pub base58ck::error::Error::IncorrectChecksum(base58ck::error::IncorrectChecksumError)
+pub base58ck::error::Error::TooShort(base58ck::error::TooShortError)
+pub fn base58ck::decode(data: &str) -> core::result::Result<alloc::vec::Vec<u8>, base58ck::error::InvalidCharacterError>
+pub fn base58ck::decode_check(data: &str) -> core::result::Result<alloc::vec::Vec<u8>, base58ck::error::Error>
+pub fn base58ck::encode(data: &[u8]) -> alloc::string::String
+pub fn base58ck::encode_check(data: &[u8]) -> alloc::string::String
+pub fn base58ck::encode_check_to_fmt(fmt: &mut core::fmt::Formatter<'_>, data: &[u8]) -> core::fmt::Result
+pub fn base58ck::error::Error::clone(&self) -> base58ck::error::Error
+pub fn base58ck::error::Error::eq(&self, other: &base58ck::error::Error) -> bool
+pub fn base58ck::error::Error::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::Error::from(e: base58ck::error::IncorrectChecksumError) -> Self
+pub fn base58ck::error::Error::from(e: base58ck::error::InvalidCharacterError) -> Self
+pub fn base58ck::error::Error::from(e: base58ck::error::TooShortError) -> Self
+pub fn base58ck::error::Error::from(never: core::convert::Infallible) -> Self
+pub fn base58ck::error::IncorrectChecksumError::clone(&self) -> base58ck::error::IncorrectChecksumError
+pub fn base58ck::error::IncorrectChecksumError::eq(&self, other: &base58ck::error::IncorrectChecksumError) -> bool
+pub fn base58ck::error::IncorrectChecksumError::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::IncorrectChecksumError::incorrect_checksum(&self) -> (u32, u32)
+pub fn base58ck::error::InvalidCharacterError::clone(&self) -> base58ck::error::InvalidCharacterError
+pub fn base58ck::error::InvalidCharacterError::eq(&self, other: &base58ck::error::InvalidCharacterError) -> bool
+pub fn base58ck::error::InvalidCharacterError::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::InvalidCharacterError::invalid_base58_character(&self) -> u8
+pub fn base58ck::error::TooShortError::clone(&self) -> base58ck::error::TooShortError
+pub fn base58ck::error::TooShortError::eq(&self, other: &base58ck::error::TooShortError) -> bool
+pub fn base58ck::error::TooShortError::fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result
+pub fn base58ck::error::TooShortError::invalid_base58_length(&self) -> usize
+pub mod base58ck
+pub mod base58ck::error
+pub struct base58ck::InvalidCharacterError
+pub struct base58ck::error::IncorrectChecksumError
+pub struct base58ck::error::InvalidCharacterError
+pub struct base58ck::error::TooShortError
+pub use base58ck::String
+pub use base58ck::Vec