src/ez/key.bend source

src/ez/key.bend on the hub · documented module

# ez/key: what a cached tool checkout and binary were made from. A checkout# is its commit. A binary is not: a pin's `bin` or `entry` builds another file# from the same commit, and another bend builds the same file differently. So# the binary's record is all three, and it is reused only when every one of# them is the one about to be built.import Base# the commit, the file handed to bend, and the bend that built ittype Stamp is Data:  Stamp{rev: String, file: String, bend: String}# the record that matches nothing: an empty commit is never reuseddef none() -> Stamp:  Stamp{"", "", ""}# the record as it is written, one field to a linedef show(key: Stamp) -> String:  match key:    case Stamp{+r, +f, +b}:      r ++ "\n" ++ f ++ "\n" ++ b ++ "\n"# exactly three lines, or no record. A cache written before the file and the# bend were recorded holds the commit alone, and that reads as no record.def read.third(+rev: String, +file: String, ls: List<&2, String>) -> Stamp:  match ls:    case []:      none()    case +b <> t:      match t:        case []:          Stamp{rev, file, b}        case _h <> _t:          none()def read.second(+rev: String, ls: List<&2, String>) -> Stamp:  match ls:    case []:      none()    case +f <> t:      read.third(rev, f, t)def read.lines(ls: List<&2, String>) -> Stamp:  match ls:    case []:      none()    case +r <> t:      read.second(r, t)# a record's text, as `show` wrote it and a file read trimmed itdef read(+text: String) -> Stamp:  read.lines(String.split(text, '\n'))# the checkout is this commit, and there is a commit at all. The checkout's# record is the commit alone: the file and the bend are the binary's business.def checkout(+was: String, +now: String) -> Bool:  Bool.and(Bool.not(String.is_empty(now)), String.eq(was, now))# the three fields the same, and a commit at all. An empty commit is a dirty# tree or a directory that is not a checkout, and those are built every time.def reuse(was: Stamp, now: Stamp) -> Bool:  match was:    case Stamp{+r0, +f0, +b0}:      match now:        case Stamp{+r1, +f1, +b1}:          Bool.and(Bool.not(String.is_empty(r1)),            Bool.and(String.eq(r0, r1),              Bool.and(String.eq(f0, f1), String.eq(b0, b1))))