https://github.com/JuliaLang/julia
Tip revision: ac49911bdb60feadcec7accca477d2146e713c11 authored by Jeff Bezanson on 15 November 2018, 02:30:31 UTC
WIP fix #29501, type intersection involving Union parameters
WIP fix #29501, type intersection involving Union parameters
Tip revision: ac49911
path.jl
# This file is a part of Julia. License is MIT: https://julialang.org/license
export
abspath,
basename,
dirname,
expanduser,
contractuser,
homedir,
isabspath,
isdirpath,
joinpath,
normpath,
realpath,
relpath,
splitdir,
splitdrive,
splitext,
splitpath
if Sys.isunix()
const path_separator = "/"
const path_separator_re = r"/+"
const path_directory_re = r"(?:^|/)\.{0,2}$"
const path_dir_splitter = r"^(.*?)(/+)([^/]*)$"
const path_ext_splitter = r"^((?:.*/)?(?:\.|[^/\.])[^/]*?)(\.[^/\.]*|)$"
splitdrive(path::String) = ("",path)
elseif Sys.iswindows()
const path_separator = "\\"
const path_separator_re = r"[/\\]+"
const path_absolute_re = r"^(?:[A-Za-z]+:)?[/\\]"
const path_directory_re = r"(?:^|[/\\])\.{0,2}$"
const path_dir_splitter = r"^(.*?)([/\\]+)([^/\\]*)$"
const path_ext_splitter = r"^((?:.*[/\\])?(?:\.|[^/\\\.])[^/\\]*?)(\.[^/\\\.]*|)$"
function splitdrive(path::String)
m = match(r"^([^\\]+:|\\\\[^\\]+\\[^\\]+|\\\\\?\\UNC\\[^\\]+\\[^\\]+|\\\\\?\\[^\\]+:|)(.*)$", path)
String(m.captures[1]), String(m.captures[2])
end
else
error("path primitives for this OS need to be defined")
end
"""
splitdrive(path::AbstractString) -> (AbstractString, AbstractString)
On Windows, split a path into the drive letter part and the path part. On Unix systems, the
first component is always the empty string.
"""
splitdrive(path::AbstractString)
"""
homedir() -> AbstractString
Return the current user's home directory.
!!! note
`homedir` determines the home directory via `libuv`'s `uv_os_homedir`. For details
(for example on how to specify the home directory via environment variables), see the
[`uv_os_homedir` documentation](http://docs.libuv.org/en/v1.x/misc.html#c.uv_os_homedir).
"""
function homedir()
path_max = 1024
buf = Vector{UInt8}(undef, path_max)
sz = RefValue{Csize_t}(path_max + 1)
while true
rc = ccall(:uv_os_homedir, Cint, (Ptr{UInt8}, Ptr{Csize_t}), buf, sz)
if rc == 0
resize!(buf, sz[])
return String(buf)
elseif rc == Base.UV_ENOBUFS
resize!(buf, sz[] - 1)
else
error("unable to retrieve home directory")
end
end
end
if Sys.iswindows()
isabspath(path::String) = occursin(path_absolute_re, path)
else
isabspath(path::String) = startswith(path, '/')
end
"""
isabspath(path::AbstractString) -> Bool
Determine whether a path is absolute (begins at the root directory).
# Examples
```jldoctest
julia> isabspath("/home")
true
julia> isabspath("home")
false
```
"""
isabspath(path::AbstractString)
"""
isdirpath(path::AbstractString) -> Bool
Determine whether a path refers to a directory (for example, ends with a path separator).
# Examples
```jldoctest
julia> isdirpath("/home")
false
julia> isdirpath("/home/")
true
```
"""
isdirpath(path::String) = occursin(path_directory_re, splitdrive(path)[2])
"""
splitdir(path::AbstractString) -> (AbstractString, AbstractString)
Split a path into a tuple of the directory name and file name.
# Examples
```jldoctest
julia> splitdir("/home/myuser")
("/home", "myuser")
```
"""
function splitdir(path::String)
a, b = splitdrive(path)
_splitdir_nodrive(a,b)
end
# Common splitdir functionality without splitdrive, needed for splitpath.
_splitdir_nodrive(path::String) = _splitdir_nodrive("", path)
function _splitdir_nodrive(a::String, b::String)
m = match(path_dir_splitter,b)
m === nothing && return (a,b)
a = string(a, isempty(m.captures[1]) ? m.captures[2][1] : m.captures[1])
a, String(m.captures[3])
end
"""
dirname(path::AbstractString) -> AbstractString
Get the directory part of a path.
# Examples
```jldoctest
julia> dirname("/home/myuser")
"/home"
```
See also: [`basename`](@ref)
"""
dirname(path::AbstractString) = splitdir(path)[1]
"""
basename(path::AbstractString) -> AbstractString
Get the file name part of a path.
# Examples
```jldoctest
julia> basename("/home/myuser/example.jl")
"example.jl"
```
See also: [`dirname`](@ref)
"""
basename(path::AbstractString) = splitdir(path)[2]
"""
splitext(path::AbstractString) -> (AbstractString, AbstractString)
If the last component of a path contains a dot, split the path into everything before the
dot and everything including and after the dot. Otherwise, return a tuple of the argument
unmodified and the empty string.
# Examples
```jldoctest
julia> splitext("/home/myuser/example.jl")
("/home/myuser/example", ".jl")
julia> splitext("/home/myuser/example")
("/home/myuser/example", "")
```
"""
function splitext(path::String)
a, b = splitdrive(path)
m = match(path_ext_splitter, b)
m === nothing && return (path,"")
a*m.captures[1], String(m.captures[2])
end
function pathsep(paths::AbstractString...)
for path in paths
m = match(path_separator_re, String(path))
m !== nothing && return m.match[1:1]
end
return path_separator
end
"""
splitpath(path::AbstractString) -> Vector{String}
Split a file path into all its path components. This is the opposite of
`joinpath`. Returns an array of substrings, one for each directory or file in
the path, including the root directory if present.
# Examples
```jldoctest
julia> splitpath("/home/myuser/example.jl")
4-element Array{String,1}:
"/"
"home"
"myuser"
"example.jl"
```
"""
function splitpath(p::String)
drive, p = splitdrive(p)
out = String[]
isempty(p) && (pushfirst!(out,p)) # "" means the current directory.
while !isempty(p)
dir, base = _splitdir_nodrive(p)
dir == p && (pushfirst!(out, dir); break) # Reached root node.
if !isempty(base) # Skip trailing '/' in basename
pushfirst!(out, base)
end
p = dir
end
if !isempty(drive) # Tack the drive back on to the first element.
out[1] = drive*out[1] # Note that length(out) is always >= 1.
end
return out
end
joinpath(a::AbstractString) = a
"""
joinpath(parts...) -> AbstractString
Join path components into a full path. If some argument is an absolute path or
(on Windows) has a drive specification that doesn't match the drive computed for
the join of the preceding paths, then prior components are dropped.
# Examples
```jldoctest
julia> joinpath("/home/myuser", "example.jl")
"/home/myuser/example.jl"
```
"""
joinpath(a::AbstractString, b::AbstractString, c::AbstractString...) = joinpath(joinpath(a,b), c...)
function joinpath(a::String, b::String)
isabspath(b) && return b
A, a = splitdrive(a)
B, b = splitdrive(b)
!isempty(B) && A != B && return string(B,b)
C = isempty(B) ? A : B
isempty(a) ? string(C,b) :
occursin(path_separator_re, a[end:end]) ? string(C,a,b) :
string(C,a,pathsep(a,b),b)
end
joinpath(a::AbstractString, b::AbstractString) = joinpath(String(a), String(b))
"""
normpath(path::AbstractString) -> AbstractString
Normalize a path, removing "." and ".." entries.
# Examples
```jldoctest
julia> normpath("/home/myuser/../example.jl")
"/home/example.jl"
```
"""
function normpath(path::String)
isabs = isabspath(path)
isdir = isdirpath(path)
drive, path = splitdrive(path)
parts = split(path, path_separator_re)
filter!(x->!isempty(x) && x!=".", parts)
while true
clean = true
for j = 1:length(parts)-1
if parts[j] != ".." && parts[j+1] == ".."
deleteat!(parts, j:j+1)
clean = false
break
end
end
clean && break
end
if isabs
while !isempty(parts) && parts[1] == ".."
popfirst!(parts)
end
elseif isempty(parts)
push!(parts, ".")
end
path = join(parts, path_separator)
if isabs
path = path_separator*path
end
if isdir && !isdirpath(path)
path *= path_separator
end
string(drive,path)
end
normpath(a::AbstractString, b::AbstractString...) = normpath(joinpath(a,b...))
"""
abspath(path::AbstractString) -> AbstractString
Convert a path to an absolute path by adding the current directory if necessary.
Also normalizes the path as in [`normpath`](@ref).
"""
abspath(a::String) = normpath(isabspath(a) ? a : joinpath(pwd(),a))
"""
abspath(path::AbstractString, paths::AbstractString...) -> AbstractString
Convert a set of paths to an absolute path by joining them together and adding the
current directory if necessary. Equivalent to `abspath(joinpath(path, paths...))`.
"""
abspath(a::AbstractString, b::AbstractString...) = abspath(joinpath(a,b...))
if Sys.iswindows()
function realpath(path::AbstractString)
p = cwstring(path)
buf = zeros(UInt16, length(p))
while true
n = ccall((:GetFullPathNameW, "kernel32"), stdcall,
UInt32, (Ptr{UInt16}, UInt32, Ptr{UInt16}, Ptr{Cvoid}),
p, length(buf), buf, C_NULL)
systemerror(:realpath, n == 0)
x = n < length(buf) # is the buffer big enough?
resize!(buf, n) # shrink if x, grow if !x
x && return transcode(String, buf)
end
end
function longpath(path::AbstractString)
p = cwstring(path)
buf = zeros(UInt16, length(p))
while true
n = ccall((:GetLongPathNameW, "kernel32"), stdcall,
UInt32, (Ptr{UInt16}, Ptr{UInt16}, UInt32),
p, buf, length(buf))
systemerror(:longpath, n == 0)
x = n < length(buf) # is the buffer big enough?
resize!(buf, n) # shrink if x, grow if !x
x && return transcode(String, buf)
end
end
else # !windows
function realpath(path::AbstractString)
p = ccall(:realpath, Ptr{UInt8}, (Cstring, Ptr{UInt8}), path, C_NULL)
systemerror(:realpath, p == C_NULL)
str = unsafe_string(p)
Libc.free(p)
return str
end
end # os-test
"""
realpath(path::AbstractString) -> AbstractString
Canonicalize a path by expanding symbolic links and removing "." and ".." entries.
"""
realpath(path::AbstractString)
if Sys.iswindows()
# on windows, ~ means "temporary file"
expanduser(path::AbstractString) = path
contractuser(path::AbstractString) = path
else
function expanduser(path::AbstractString)
y = iterate(path)
y === nothing && return path
c, i = y
c != '~' && return path
y = iterate(path, i)
y === nothing && return homedir()
y[1] == '/' && return homedir() * path[i:end]
throw(ArgumentError("~user tilde expansion not yet implemented"))
end
function contractuser(path::AbstractString)
home = homedir()
if path == home
return "~"
elseif startswith(path, home)
return joinpath("~", relpath(path, home))
else
return path
end
end
end
"""
expanduser(path::AbstractString) -> AbstractString
On Unix systems, replace a tilde character at the start of a path with the current user's home directory.
"""
expanduser(path::AbstractString)
"""
contractuser(path::AbstractString) -> AbstractString
On Unix systems, if the path starts with `homedir()`, replace it with a tilde character.
"""
contractuser(path::AbstractString)
"""
relpath(path::AbstractString, startpath::AbstractString = ".") -> AbstractString
Return a relative filepath to `path` either from the current directory or from an optional
start directory. This is a path computation: the filesystem is not accessed to confirm the
existence or nature of `path` or `startpath`.
"""
function relpath(path::String, startpath::String = ".")
isempty(path) && throw(ArgumentError("`path` must be specified"))
isempty(startpath) && throw(ArgumentError("`startpath` must be specified"))
curdir = "."
pardir = ".."
path == startpath && return curdir
path_arr = split(abspath(path), path_separator_re)
start_arr = split(abspath(startpath), path_separator_re)
i = 0
while i < min(length(path_arr), length(start_arr))
i += 1
if path_arr[i] != start_arr[i]
i -= 1
break
end
end
pathpart = join(path_arr[i+1:something(findlast(x -> !isempty(x), path_arr), 0)], path_separator)
prefix_num = something(findlast(x -> !isempty(x), start_arr), 0) - i - 1
if prefix_num >= 0
prefix = pardir * path_separator
relpath_ = isempty(pathpart) ?
(prefix^prefix_num) * pardir :
(prefix^prefix_num) * pardir * path_separator * pathpart
else
relpath_ = pathpart
end
return isempty(relpath_) ? curdir : relpath_
end
relpath(path::AbstractString, startpath::AbstractString) =
relpath(String(path), String(startpath))
for f in (:isabspath, :isdirpath, :splitdir, :splitdrive, :splitext, :normpath, :abspath)
@eval $f(path::AbstractString) = $f(String(path))
end