A piggy bank of commands, fixes, succinct reviews, some mini articles and technical opinions from a (mostly) Perl developer.

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Showing posts with label sort. Show all posts
Showing posts with label sort. Show all posts

See all commit messages in svn log

After merging a branch to trunk, subversion does not include commit logs from branches in the trunk log. With a little work it can be persuaded to display the log in a more useful way, see "svnlogg" perl script below.

When viewing this log output you may want to see the diff of one of the changes and naively type:

    svn diff -c 69271

...this may produce no output. However, if you type this intead:

    svn diff -c 69271 https://www.example.com/repo/branches/feature_xyz

...then you will see the expected output.

How to determine the branch name from the commit message is left as an exercise for the reader.


"svnlogg" perl script:

#!/usr/bin/env perl

# First, get all the commits.
# -v shows the filenames of changed files,
# -g shows commits from all merged branches.

my $LOG_TEMP = "/tmp/log.txt";

system("svn log -v -g > $LOG_TEMP");

# Then split the list into individual commits, filter out ones we don't want to see, and sort by date:

open(my $fh,"<",$LOG_TEMP) or die "cannot open file $LOG_TEMP";
local $/="------------------------------------------------------------------------"; # define the record separator
my @a = <$fh>; # populate an array with the commit messages
foreach my $aa (
    sort {
        # sort the commits by date (descending)
        my ($c) = $a =~ /\s\|\s(\d\d\d\d\-\d\d\-\d\d)\s/; # extract date field
        my ($d) = $b =~ /\s\|\s(\d\d\d\d\-\d\d\-\d\d)\s/; #
        $d cmp $c
    } @a
) {
    # exclude unwanted messages, especially the hundreds of "remove svn:mergeinfo"
    # also exclude the commit messages we use by convention in our organisation
    # to refer to branches and merges
    if ($aa !~ /(remove svn:mergeinfo|branching|final pull)/i) {
        print "$aa\n";
    }
}

Depending on your hardware it may be unusably slow, so pipe it into a file for viewing later.

Shuffle lines in bash

#!/bin/bash
# Print out the lines from a file, in a random order
FILE=$1
if [[ -z $FILE ]]
then
    echo "usage: shuffle [filename]"
    exit 1
fi
for i in `cat $FILE`; do echo "$RANDOM $i"; done | sort | sed -r 's/^[0-9]+ //'

Thanks

Dedupe lines in place

in vim, select a list of values with shift-V (visual mode), and then type :sort u to sort them and remove duplicates.

Sorting in Perl

Custom sorting method:

@sorted = sort { 
  if ($a eq 'aardvark') { return 1; }
  elsif ($b eq 'aardvark') { return -1; }
  else { return $a cmp $b; } 
} @words;

Remember to test for the special case for both $a and $b.


Thanks

Min/Max for XSLT

Obtaining the MIN:
<!-- Create a variable named $minEventDate containing the MIN date -->
<xsl:variable name="minEventDate">
<xsl:for-each select="event">
<xsl:sort select="@date" data-type="text" order="ascending" />
<xsl:if test="position() = 1">
<xsl:value-of select="@date" />
</xsl:if>
</xsl:for-each>
</xsl:variable>

Obtaining the MAX:
<!-- Create a variable named $maxEventDate containing the MAX date -->
<xsl:variable name="maxEventDate">
<xsl:for-each select="event">
<xsl:sort select="@date" data-type="text" order="descending" />
<xsl:if test="position() = 1">
<xsl:value-of select="@date" />
</xsl:if>
</xsl:for-each>
</xsl:variable>