Version 0.2.0: RDB_ICASE, Changelog, --version, angepasste Man-Pages

lib/rdb.rb

@@ -7,6 +7,7 @@ require 'open3'
 require 'date'
 require 'tmpdir'
 require 'fileutils'
+require_relative 'rdb/version'
 
 module Rdb
   ROOT = File.expand_path('..', __dir__)
@@ -16,6 +17,21 @@ module Rdb
   COMMANDS = {}
 
   class << self
+    # RDB_ICASE=1 makes column names match without regard to case.  An exact
+    # match always wins; several case-insensitive matches are an error.
+    def icase?
+      !%w[0 no false].include?(ENV['RDB_ICASE'].to_s.downcase) && !ENV['RDB_ICASE'].to_s.empty?
+    end
+
+    def column_index(head, name)
+      exact = head.index(name)
+      return exact if exact || !icase?
+
+      hits = head.each_index.select { |i| head[i].casecmp?(name) }
+      die "column name '#{name}' is ambiguous: #{hits.map { |i| head[i] }.join(', ')}" if hits.size > 1
+      hits.first
+    end
+
     def die(msg)
       abort "#{File.basename($PROGRAM_NAME)}: #{msg}"
     end

lib/rdb/cmd/relational.rb

@@ -15,8 +15,9 @@ Rdb.register('column', 'Display columns of a table in any order', 'column [ Colu
   t = table_in
   next t.write if args.empty?
 
-  idx = args.map { |a| t.head.index(a) }
-  t.with(head: args, rows: t.rows.map { |r| idx.map { |i| i ? r[i] : '' } }).write
+  idx = args.map { |a| Rdb.column_index(t.head, a) }
+  head = args.each_with_index.map { |a, n| idx[n] ? t.head[idx[n]] : a }
+  t.with(head: head, rows: t.rows.map { |r| idx.map { |i| i ? r[i] : '' } }).write
 end
 Rdb.alias_for('project', 'column')
 

lib/rdb/env.rb

@@ -40,6 +40,24 @@ module Rdb
 
     # Replace column names in an awk expression with $N, leaving strings,
     # regexes and other identifiers alone.
+    AWK_WORDS = %w[BEGIN END NR NF FS OFS ORS RS FNR FILENAME SUBSEP RSTART RLENGTH ENVIRON ARGC ARGV
+                   if else while for do in break continue next exit return function delete getline
+                   print printf length substr index split sub gsub match sprintf sin cos atan2 exp log
+                   sqrt int rand srand tolower toupper system].freeze
+
+    # With RDB_ICASE, a word that is not an awk keyword or function call may
+    # name a column in any case, provided that exactly one column fits.
+    def icase_column(names, expr, i)
+      return unless Rdb.icase?
+
+      word = expr[i..][/\A\w+/].to_s
+      return if word.empty? || AWK_WORDS.include?(word) || expr[i + word.size..].to_s.match?(/\A\s*\(/)
+
+      hits = names.select { |n, _| n.casecmp?(word) }
+      Rdb.die "column name '#{word}' is ambiguous: #{hits.map(&:first).join(', ')}" if hits.size > 1
+      hits.first
+    end
+
     def to_awk(expr, head)
       names = head.each_with_index.sort_by { |n, _| -n.size }
       out = +''
@@ -59,6 +77,7 @@ module Rdb
           i = j + 1
         elsif c.match?(/[A-Za-z_#]/) && (i.zero? || !expr[i - 1].match?(/[\w$]/))
           hit = names.find { |n, _| !n.empty? && expr[i, n.size] == n && !expr[i + n.size].to_s.match?(/\w/) }
+          hit ||= icase_column(names, expr, i)
           if hit
             out << "$#{hit[1] + 1}"
             i += hit[0].size

lib/rdb/fast.rb

@@ -53,7 +53,7 @@ module Rdb
       end
 
       def column(name)
-        @head.index(name) || Rdb.die("#{path}: no column named '#{name}'")
+        Rdb.column_index(@head, name) || Rdb.die("#{path}: no column named '#{name}'")
       end
 
       def row_at(offset)

lib/rdb/table.rb

@@ -60,7 +60,7 @@ module Rdb
     end
 
     def index_of(name)
-      @head.index(name) || Rdb.die("no column named '#{name}'")
+      Rdb.column_index(@head, name) || Rdb.die("no column named '#{name}'")
     end
 
     def to_s

lib/rdb/version.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+module Rdb
+  VERSION = '0.2.0'
+end