view tests/test-releasenotes-parsing.t @ 44363:f7459da77f23

nodemap: introduce an option to use mmap to read the nodemap mapping

The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.

This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).

Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:

Before:

 * do not use the persistent nodemap
 * use the CPython implementation of the index for nodemap
 * use mmapping of the changelog index

After:

 * use the MixedIndex Rust code, with the NodeTree object for nodemap access
   (still in review)
 * use the persistent nodemap data from disk
 * access the persistent nodemap data through mmap
 * use mmapping of the changelog index

The persistent nodemap greatly speed up  most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.

Here are some numbers (in seconds) for the reference copy of mozilla-try:

Revset            Before   After     abs-change speedup

-10000:           0.004622 0.005532   0.000910  ×   0.83
-10:              0.000050 0.000132   0.000082  ×   0.37
tip               0.000052 0.000085   0.000033  ×   0.61
0 + (-10000:)     0.028222 0.005337  -0.022885  ×   5.29
0                 0.023521 0.000084  -0.023437  × 280.01
(-10000:) + 0     0.235539 0.005308  -0.230231  ×  44.37
(-10:) + :9       0.232883 0.000180  -0.232703  ×1293.79
(-10000:) + (:99) 0.238735 0.005358  -0.233377  ×  44.55
:99 + (-10000:)   0.317942 0.005593  -0.312349  ×  56.84
:9 + (-10:)       0.313372 0.000179  -0.313193  ×1750.68
:9                0.316450 0.000143  -0.316307  ×2212.93


On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.

Here are some numbers (in seconds) for the reference copy of mercurial:

Revset            Before   After     abs-change speedup
-10:              0.000065 0.000097   0.000032  × 0.67
tip               0.000063 0.000078   0.000015  × 0.80
0                 0.000561 0.000079  -0.000482  × 7.10
-10000:           0.004609 0.003648  -0.000961  × 1.26
0 + (-10000:)     0.005023 0.003715  -0.001307  × 1.35
(-10:) + :9       0.002187 0.000108  -0.002079  ×20.25
(-10000:) + 0     0.006252 0.003716  -0.002536  × 1.68
(-10000:) + (:99) 0.006367 0.003707  -0.002660  × 1.71
:9 + (-10:)       0.003846 0.000110  -0.003736  ×34.96
:9                0.003854 0.000099  -0.003755  ×38.92
:99 + (-10000:)   0.007644 0.003778  -0.003866  × 2.02

Differential Revision: https://phab.mercurial-scm.org/D7894

#require fuzzywuzzy

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > releasenotes=
  > EOF

Bullet point with a single item spanning a single line

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > * Bullet point item with a single line
  > EOF
  section: feature
    bullet point:
      paragraph: Bullet point item with a single line

Bullet point that spans multiple lines.

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > * Bullet point with a paragraph
  >   that spans multiple lines.
  > EOF
  section: feature
    bullet point:
      paragraph: Bullet point with a paragraph that spans multiple lines.

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > * Bullet point with a paragraph
  >   that spans multiple lines.
  > 
  >   And has an empty line between lines too.
  >   With a line cuddling that.
  > EOF
  section: feature
    bullet point:
      paragraph: Bullet point with a paragraph that spans multiple lines.
      paragraph: And has an empty line between lines too. With a line cuddling that.

Multiple bullet points. With some entries being multiple lines.

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > * First bullet point. It has a single line.
  > 
  > * Second bullet point.
  >   It consists of multiple lines.
  > 
  > * Third bullet point. It has a single line.
  > EOF
  section: feature
    bullet point:
      paragraph: First bullet point. It has a single line.
    bullet point:
      paragraph: Second bullet point. It consists of multiple lines.
    bullet point:
      paragraph: Third bullet point. It has a single line.

Bullet point without newline between items

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > * First bullet point
  > * Second bullet point
  >   And it has multiple lines
  > * Third bullet point
  > * Fourth bullet point
  > EOF
  section: feature
    bullet point:
      paragraph: First bullet point
    bullet point:
      paragraph: Second bullet point And it has multiple lines
    bullet point:
      paragraph: Third bullet point
    bullet point:
      paragraph: Fourth bullet point

Sub-section contents are read

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > First Feature
  > -------------
  > 
  > This is the first new feature that was implemented.
  > 
  > And a second paragraph about it.
  > 
  > Second Feature
  > --------------
  > 
  > This is the second new feature that was implemented.
  > 
  > Paragraph two.
  > 
  > Paragraph three.
  > EOF
  section: feature
    subsection: First Feature
      paragraph: This is the first new feature that was implemented.
      paragraph: And a second paragraph about it.
    subsection: Second Feature
      paragraph: This is the second new feature that was implemented.
      paragraph: Paragraph two.
      paragraph: Paragraph three.

Multiple sections are read

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > * Feature 1
  > * Feature 2
  > 
  > Bug Fixes
  > =========
  > 
  > * Fix 1
  > * Fix 2
  > EOF
  section: feature
    bullet point:
      paragraph: Feature 1
    bullet point:
      paragraph: Feature 2
  section: fix
    bullet point:
      paragraph: Fix 1
    bullet point:
      paragraph: Fix 2

Mixed sub-sections and bullet list

  $ hg debugparsereleasenotes - << EOF
  > New Features
  > ============
  > 
  > Feature 1
  > ---------
  > 
  > Some words about the first feature.
  > 
  > Feature 2
  > ---------
  > 
  > Some words about the second feature.
  > That span multiple lines.
  > 
  > Other Changes
  > -------------
  > 
  > * Bullet item 1
  > * Bullet item 2
  > EOF
  section: feature
    subsection: Feature 1
      paragraph: Some words about the first feature.
    subsection: Feature 2
      paragraph: Some words about the second feature. That span multiple lines.
    bullet point:
      paragraph: Bullet item 1
    bullet point:
      paragraph: Bullet item 2

Warn user in case of unexpected block while parsing

  $ hg init relnotes-warn
  $ cd relnotes-warn
  $ touch feature1
  $ hg -q commit -A -l - << EOF
  > commit 1
  > 
  > .. feature::
  > 
  >    new feature added.
  >     some words about the feature.
  > EOF

  $ hg releasenote -r .
  changeset a4251905c440: unexpected block in release notes directive feature
  New Features
  ============
  
  * new feature added.  some words about the feature.

  $ cd ..