Still alias function shadows builtin function (of any arity) by name. This
allows to detect argument error as such, but might be a bit inconvenient if
user wants to overload heads() for example. If needed, maybe we can add some
config/revset syntax to import builtin function to alias namespace.
The functions table is keyed by name, not by (name, arity) pair. That's mainly
because std collections require keys to be Borrow, and a pair of borrowed
values is incompatible with owned pair. Another reason is it makes easy to look
up overloads by name.
Alias overloading could also be achieved by adding default parameters, but that
will complicate the implementation a bit more, and can't prevent shadowing of
0-ary immutable_heads().
Closes#2966
We can add a separate precedence/associativity table, but I think the ordered
list is good enough. Nullary :: and .. have no binding, but inserted after the
infix versions for brevity.
More tests will be added later as "branch list" templates.
In "log" template, we might want to see the number of "local" commits ahead
of any tracked remotes. It can be implemented later in a similar way (or as a
nested remote_refs list.)
We'll probably add binary comparison operators at some point, but this patch
also adds size_hint.zero() method. Otherwise, we'll have to write
"if(x.upper() && x.upper() == 0, ..)" to deal with None.
The resulting "branch list" template will look like:
```
separate(", ",
if(!ref.tracking_ahead_count().zero(),
if(ref.tracking_ahead_count().exact(),
"ahead by " ++ ref.tracking_ahead_count().exact() ++ " commits",
"ahead by at least " ++ ref.tracking_ahead_count().lower() ++ " commits")),
if(!ref.tracking_behind_count().zero(),
if(ref.tracking_behind_count().exact(),
"behind by " ++ ref.tracking_behind_count().exact() ++ " commits",
"behind by at least " ++ ref.tracking_behind_count().lower() ++ " commits")),
)
```
I considered adding RefTarget template type, but some of the methods naturally
fit to RefName. For example, a conflicted branch name is decorated as "??", so
it makes sense to add branch.conflict() instead of branch.target().conflict().
I'm not pretty sure how many RefName methods we'll need to add to port the
current branch listing, but there will be .tracked(), .tracking_local_present(),
.ahead_by(), and .behind_by().
Since fileset/revset/template expressions are specified as command-line
arguments, it's sometimes convenient to use single quotes instead of double
quotes. Various scripting languages parse single-quoted strings in various ways,
but I choose the TOML rule because it's simple and practically useful. TOML is
our config language, so copying the TOML syntax would be less surprising than
borrowing it from another language.
https://github.com/toml-lang/toml/issues/188
Expose the information we now record, to allow changing the default "snapshot
working copy" message or to make snapshots more compact/less distracting in
the log
This can be used to flatten nested "if()"s. It's not exactly the same as "case"
or "switch" expression, but works reasonably well in template. It's not uncommon
to show placeholder text in place of an empty content, and a nullish value
(e.g. empty string, list, option) is usually rendered as an empty text.
I think Option<Commit> is the simplest encoding of the log node.
The behavior of an Option type is closer to nullable types rather than the
Option in Rust. I don't think we would want to write opt.map(|x| x.f()) or
opt.unwrap().f(). We can of course add opt?.f() syntax, but it will be a short
for "if(opt, opt.f())"?
I'm going to add string.len() method which will return a length in bytes. The
number of the UTF-8 code points is useless metrics, and strings here are often
ASCII bytes, so let's simply use byte indices in substr().
If the given index is not at a char boundary, it will be rounded. I considered
making it an error, but that would be annoying. I would want to see something
printed by author.name().substr() even if it contained latin characters.
I've extracted index normalization function which might be used by other string
methods. The remaining part of substr() is trivial, so inlined it.
This allows us to call alias function with the top-level object.
For convenience, all self.<method>()s are available as keywords. I don't think
we'll want to deprecate them. It would be tedious if we had to specify
-T'self.commit_id()' instead of -Tcommit_id.
Follows up 9702a425e5 "Allow negative numbers in the template grammar."
Since we've added parsing rules for operator expressions, it makes sense to
parse unary '-' as operator.
I'll probably add infix logical operators later, but the surround() function
is still useful because we don't have to repeat the condition:
if(x || y, "<" ++ separate(" ", x, y) ++ ">")
surround("<", ">", separate(" ", x, y))
It can't be used if we want to add placeholder text, though:
if(x || y, "<" ++ separate(" ", x, y) ++ ">", "(none)")
Closes#2924
Both local and remote refs are backed by the same value type since we'll need
some kind of runtime abstraction to represent "branches" keyword (which is a
list of local + remote branches.) It's tedious to implement separate
local/remote/both ref types.
The "unsynced" flag is inverted just because the positive term is slightly
easier to document.
I'm going to change "branches" to return a list instead of formatted string,
and I don't think "if(branches, ..)" should be invalidated by that. Perhaps,
a container type like String, Vec<T>, Option<T> can implement the cast.
We are a little weird about which string escapes we support, and we don't
support raw strings. I thought this might be worth documenting.
Inspired by https://github.com/martinvonz/jj/pull/2251
Similar to other boolean flags, such as "working_copy" or "empty".
We could test something like
`"0000000000000000000000000000000000000000".contains(commit_id)`
like I did for myself, but first of all this is ugly, and secondly the root
commit id is not guaranteed to be 40 zeroes as custom backend implementations
could have some other root.
This involves a little hack to insert a lambda parameter 'x' to be used at
keyword position. If the template language were dynamically typed (and were
interpreted), .map() implementation would be simpler. I considered that, but
interpreter version has its own warts (late error reporting, uneasy to cache
static object, etc.), and I don't think the current template engine is
complex enough to rewrite from scratch.
.map() returns template, which can't be join()-ed. This will be fixed later.
The parameter order follows indent()/label() functions, but this might be
a bad idea because fill() is more likely to have optional parameters. We can
instead add template.fill(width) method as well as .indent(prefix). If we take
this approach, we'll probably need to add string.fill()/indent() methods,
and/or implicit cast at method resolution. The good thing about the method
syntax is that we can add string.refill(), etc. for free, without inventing
generic labeled template functions.
For #1043, I think it's better to add a config like ui.log-word-wrap = true.
We could add term_width/graph_width keywords to the templater, but the
implementation would be more complicated, and is difficult to use for the
basic use case. Unlike Mercurial, our templater doesn't have a context map
to override the graph_width stub.
A list type isn't so useful without a map operation, but List<CommitId>
is at least printable. Maybe we can experiment with it to craft a map
operation.
If a map operation is introduced, this keyword might be replaced with
"parents.map(|commit| commit.commit_id)", where parents is of List<Commit>
type, and the .map() method will probably return List<Template>.
The argument order is different from Mercurial's indent() function. I think
indent(prefix, content) is more readable for lengthy content. However,
indent(content, prefix, ...) might be better if we want to add an optional
firstline_prefix argument.
