refactor(tvix/libutil): Mark single-argument constructors explicit r/1704

This is the clang-tidy lint 'google-explicit-constructor'.

There's a whole bunch of breakage that was introduced by this, and we
had to opt out a few types of this (esp. the string formatting crap).

In some cases minor other changes have been done to keep the code
working, instead of converting between types (e.g. an explicit
comparison operator implementation for nix::Pid).

Change-Id: I12e1ca51a6bc2c882dba81a2526b9729d26988e7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1832
Tested-by: BuildkiteCI
Reviewed-by: kanepyork <rikingcoding@gmail.com>
Reviewed-by: glittershark <grfn@gws.fyi>

1 files changed, 4 insertions, 4 deletions

diff --git a/third_party/nix/src/libutil/hash.hh b/third_party/nix/src/libutil/hash.hh
index 6fbeec5b47fb..8b52ac657e7f 100644
--- a/third_party/nix/src/libutil/hash.hh
+++ b/third_party/nix/src/libutil/hash.hh
@@ -42,14 +42,14 @@ struct Hash {
   Hash(){};
 
   /* Create a zero-filled hash object. */
-  Hash(HashType type) : type(type) { init(); };
+  explicit Hash(HashType type) : type(type) { init(); };
 
   /* Initialize the hash from a string representation, in the format
      "[<type>:]<base16|base32|base64>" or "<type>-<base64>" (a
      Subresource Integrity hash expression). If the 'type' argument
      is htUnknown, then the hash type must be specified in the
      string. */
-  Hash(std::string_view s, HashType type = htUnknown);
+  explicit Hash(std::string_view s, HashType type = htUnknown);
 
   /* Status-returning version of above constructor */
   static absl::StatusOr<Hash> deserialize(std::string_view s,
@@ -61,7 +61,7 @@ struct Hash {
   void init();
 
   /* Check whether a hash is set. */
-  operator bool() const { return type != htUnknown; }
+  explicit operator bool() const { return type != htUnknown; }
 
   /* Check whether two hash are equal. */
   bool operator==(const Hash& h2) const;
@@ -136,7 +136,7 @@ class HashSink : public BufferedSink {
   unsigned long long bytes;
 
  public:
-  HashSink(HashType ht);
+  explicit HashSink(HashType ht);
   HashSink(const HashSink& h);
   ~HashSink();
   void write(const unsigned char* data, size_t len);