[SR-1014] Format of assertion failure output is not perfect

[swift-ci]

Previous ID	SR-1014
Radar	None
Original Reporter	zge (JIRA User)
Type	Improvement

Environment

Apple Swift version 2.2 (swiftlang-703.0.18.1 clang-703.0.29)

Additional Detail from JIRA

| | | |------------------|-----------------| |Votes | 0 | |Component/s | Standard Library | |Labels | Improvement | |Assignee | None | |Priority | Medium | md5: 9068f874a4c60373f6252c0cd61b70bb

Issue Description:

When one calls

assert(booleanExpression, message)

and the booleanExpression is evaluated to be false, assertion will be failed and the output should be like this:

assertion failed: message file: path/to/file, line: lineNumber

but actually, the output is like this (notice the position and the missing of the colons):

assertion failed: message: file path/to/file, line lineNumber

For example:

let age = -2
assert(age >= 0), "A person's age cannot be less than zero.")

the output is:

assertion failed: A person's age cannot be less than zero.: file /var/folders/cj/3vtljk7s5pndy1wrwx88jpmc0000gn/T/lldb/938/repl79.swift, line 46

ideally, this above output should be formatted to:

assertion failed: A person's age cannot be less than zero. file: /var/folders/cj/3vtljk7s5pndy1wrwx88jpmc0000gn/T/lldb/938/repl79.swift, line: 46

[belkadan]

Personally, I'd prefer a syntax more like compiler diagnostics:

\(file):\(line): assertion failed: \(message)

I believe the current format comes from C:

Assertion failed: (0 && "hello!"), function main, file <stdin>, line 4.

although with a few slight differences.

So it's not clear that yours is "better".

[swift-ci]

Comment by Zhifu Ge (JIRA)

I don't have a preference over your format or that of C's.

What I meant by "not perfect" is:
1) the second colon is before rather than after the word "file"
2) there is not colon after the word "line", not consistent with other parts of the line.

[swift-ci]

Comment by Zhifu Ge (JIRA)

We don't need to change the format, just need to put colons in the right places.