Merge branch 'master' into sk/protocol

.gitignore

@@ -9,3 +9,4 @@ docs/build
 /docs/src/repl.md
 .DS_Store
 /test/registries/*
+/test/loaded_depot/*

docs/src/api.md

@@ -4,6 +4,16 @@ This section describes the function interface, or "API mode",
 for interacting with Pkg.jl. The function API is recommended
 for non-interactive usage, for example in scripts.
 
+## General API Reference
+
+Certain options are generally useful and can be specified in any API call.
+You can specify these options by setting keyword arguments.
+
+### Redirecting output
+
+Use the `io::IOBuffer` keyword argument to redirect Pkg output.
+For example, `Pkg.add("Example"; io=devnull)` will discard any output produced by the `add` call.
+
 ## Package API Reference
 
 In the REPL mode, packages (with associated version, UUID, URL etc) are parsed from strings,

docs/src/artifacts.md

@@ -1,5 +1,8 @@
 # [**8.** Artifacts](@id Artifacts)
 
+!!! compat "Julia 1.3"
+    Pkg's artifacts functionality requires at least Julia 1.3.
+
 `Pkg` can install and manage containers of data that are not Julia packages.  These containers can contain platform-specific binaries, datasets, text, or any other kind of data that would be convenient to place within an immutable, life-cycled datastore.
 These containers, (called "Artifacts") can be created locally, hosted anywhere, and automatically downloaded and unpacked upon installation of your Julia package.
 This mechanism is also used to provide the binary dependencies for packages built with [`BinaryBuilder.jl`](https://github.com/JuliaPackaging/BinaryBuilder.jl).

docs/src/compatibility.md

@@ -29,7 +29,7 @@ The union of multiple version specifiers can be formed by comma separating indiv
 [compat]
 Example = "1.2, 2"
 ```
-will result in `[1.2.0, 3.0.0)`.
+will result in `[1.2.0, 3.0.0)`.  Note leading zeros are treated differently, e.g. `Example = "0.2, 1"` would only result in `[0.2.0-0.3.0, 1.0.0-2.0.0]`. See the next section for more information on versions with leading zeros.
 
 ### Behavior of versions with leading zeros (0.0.x and 0.x.y)
 
@@ -46,7 +46,7 @@ minor versions are not considered compatible, so the version 0.3.0 might have br
 Example = "0.0.1"
 ```
 
-results in a versionbound on `Example` as `[0.0.1, 0.02)` (which is equivalent to only the version 0.0.1), while the
+results in a versionbound on `Example` as `[0.0.1, 0.0.2)` (which is equivalent to only the version 0.0.1), while the
 `[compat]` entry:
 
 ```julia

docs/src/toml-files.md

@@ -6,8 +6,8 @@ and `Manifest.toml` are written in [TOML](https://github.com/toml-lang/toml) (he
 UUIDs etc.
 
 !!! note
-    The `Project.toml` and `Manifest.toml` files are not only used by the package manager,
-    they are also used by Julia's code loading, and determines e.g. what `using Example`
+    The `Project.toml` and `Manifest.toml` files are not only used by the package manager;
+    they are also used by Julia's code loading, and determine e.g. what `using Example`
     should do. For more details see the section about
     [Code Loading](https://docs.julialang.org/en/v1/manual/code-loading/)
     in the Julia manual.
@@ -41,6 +41,9 @@ uuid = "7876af07-990d-54b4-ab0e-23690620f79a"
 ```
 The `uuid` field is mandatory for packages.
 
+!!! note
+    It is recommended that `UUIDs.uuid4()` is used to generate random UUIDs.
+
 
 ### The `version` field
 
@@ -74,7 +77,7 @@ Example = "7876af07-990d-54b4-ab0e-23690620f79a"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 ```
 
-Typically it is not needed to manually add entries to the `[deps]` section, this is instead
+Typically it is not needed to manually add entries to the `[deps]` section; this is instead
 handled by Pkg operations such as `add`.
 
 
@@ -105,10 +108,10 @@ julia = "1.1"
 ## `Manifest.toml`
 
 The manifest file is an absolute record of the state of the packages in the environment.
-It includes exact information about (direct and indirect) dependencies of the project, and
-given a `Project.toml` + `Manifest.toml` pair it is possible to instantiate the exact same
-package environment, which is very useful for reproducibility,
-see [`Pkg.instantiate`](@ref).
+It includes exact information about (direct and indirect) dependencies of the project. 
+Given a `Project.toml` + `Manifest.toml` pair, it is possible to instantiate the exact same
+package environment, which is very useful for reproducibility. 
+For the details, see [`Pkg.instantiate`](@ref).
 
 !!! note
     The `Manifest.toml` file is generated and maintained by Pkg and, in general, this file
@@ -118,7 +121,7 @@ see [`Pkg.instantiate`](@ref).
 ### `Manifest.toml` entries
 
 Each dependency has its own section in the manifest file, and its content varies depending
-on how the dependency was added to the environment, see the examples below. Every
+on how the dependency was added to the environment. Every
 dependency section includes a combination of the following entries:
 
 * `uuid`: the [UUID](https://en.wikipedia.org/wiki/Universally_unique_identifier)
@@ -207,7 +210,7 @@ source tree is directly reflected.
 
 #### Pinned package
 
-Pinned packages are also recorded in the manifest file, the resulting
+Pinned packages are also recorded in the manifest file; the resulting
 dependency section for e.g. `pkg> add Example; pin Example` looks like:
 
 ```toml

ext/TOML/src/TOML.jl

@@ -12,7 +12,7 @@ module TOML
 
     "Convert `TOML.Table` to `Dict{String,Any}`"
     function table2dict(tbl::Union{Nothing,Table})
-        tbl == nothing && return Dict{String,Any}()
+        tbl === nothing && return Dict{String,Any}()
         return table2dict(get(tbl))
     end
 

src/API.jl

@@ -11,7 +11,7 @@ import LibGit2
 import ..depots, ..depots1, ..logdir, ..devdir
 import ..Operations, ..Display, ..GitTools, ..Pkg, ..UPDATED_REGISTRY_THIS_SESSION
 using ..Types, ..TOML
-using Pkg.Types: VersionTypes
+using ..Types: VersionTypes
 using ..BinaryPlatforms
 using ..Artifacts: artifact_paths
 
@@ -394,7 +394,7 @@ function gc(ctx::Context=Context(); collect_delay::Period=Day(30), kwargs...)
 
         # Collect the locations of every package referred to in this manifest
         pkg_dir(uuid, entry) = Operations.find_installed(entry.name, uuid, entry.tree_hash)
-        return [pkg_dir(u, e) for (u, e) in manifest if e.tree_hash != nothing]
+        return [pkg_dir(u, e) for (u, e) in manifest if e.tree_hash !== nothing]
     end
 
     function process_artifacts_toml(path)
@@ -434,7 +434,7 @@ function gc(ctx::Context=Context(); collect_delay::Period=Day(30), kwargs...)
         for index_file in index_files
             # Check to see if it's still alive
             paths = process_func(index_file)
-            if paths != nothing
+            if paths !== nothing
                 # Print the path of this beautiful, extant file to the user
                 println("        $(Types.pathrepr(index_file))")
                 append!(marked_paths, paths)
@@ -682,7 +682,7 @@ function precompile(ctx::Context)
     for pkg in pkgids
         paths = Base.find_all_in_cache_path(pkg)
         sourcepath = Base.locate_package(pkg)
-        sourcepath == nothing && continue
+        sourcepath === nothing && continue
         # Heuristic for when precompilation is disabled
         occursin(r"\b__precompile__\(\s*false\s*\)", read(sourcepath, String)) && continue
         stale = true
@@ -906,8 +906,18 @@ end
 UndoState() = UndoState(0, UndoState[])
 const undo_entries = Dict{String, UndoState}()
 const max_undo_limit = 50
-
-function add_snapshot_to_undo(env = EnvCache())
+const saved_initial_snapshot = Ref(false)
+
+function add_snapshot_to_undo(env=nothing)
+    # only attempt to take a snapshot if there is
+    # an active project to be found
+    if env === nothing
+        if Base.active_project() === nothing
+            return
+        else
+            env = EnvCache()
+        end
+    end
     state = get!(undo_entries, env.project_file) do
         UndoState()
     end
@@ -929,7 +939,7 @@ function redo_undo(ctx, mode::Symbol, direction::Int)
     @assert direction == 1 || direction == -1
     state = get(undo_entries, ctx.env.project_file, nothing)
     state === nothing && pkgerror("no undo state for current project")
-    state.idx == (mode == :redo ? 1 : length(state.entries)) && pkgerror("$mode: no more states left")
+    state.idx == (mode === :redo ? 1 : length(state.entries)) && pkgerror("$mode: no more states left")
 
     state.idx += direction
     snapshot = state.entries[state.idx]