10. The computer program product according to claim 7 , wherein the test categories include determination of validity of a sorting result of the character strings in accordance with the order of characters defined for the second language, and fonts used for the determination of validity of the sorting result regard the second group as the test object group, and relate character shapes indicating the order defined for the characters for the second language corresponding to said character codes to the plurality of character codes for the second group, respectively.
7. A computer program product stored on a non-transitory computer readable storage medium for testing international software that conducts processing with reference to an externalized resource file, the computer program product being configured to be able, when executed on a computer, to cause the computer to execute the steps of: reading data from an externalized resource file written in a first language; generating a test resource file written in a second language from the externalized resource file by converting characters of the first language contained in the data into characters of the second language with reference to a conversion table in which the characters of the first language are associated one-for-one with the characters of the second language; creating character codes for representing the characters of the first language and the characters of the second language; creating mapping between the first language and the second language such that the number of character codes for the second language is greater than the number of character codes for the first language; extracting a key attached to a character string from an item read from the externalized resource file, and to assign the extracted key to a variable key; writing the variable key to the test resource file; assigning variables to each of the characters in the character string and to compare each of the characters in the character string with a string boundary character; executing the internationalization software; and testing output information including character codes outputted from the internationalization software and displayed on a display screen with one of a plurality of fonts prepared for each test category of the internationalization software; classifying the character codes included in the output information to one of three groups: a first group composed of a plurality of character codes corresponding to a first plurality of characters for the first language, which are not supposed to be included in the output information; a second group composed of a second plurality of character codes corresponding to the characters for the second language included in the conversion table, which are supposed to be included in the output information; and a third group composed of a plurality of character codes not corresponding to any of the first plurality of characters for the first language and the second plurality of characters for the second language included in the conversion table, and which are not supposed to be included in the output information, confirming character strings included in the externalized resource file, wherein the plurality of fonts except for fonts used for the character string confirmation relate a first same character shape or a plurality of different character shapes to the character codes included in any one group of the first to the third groups, which are test objects in corresponding test items, respectively, and, relate a second same character shape, which is different from the first same character shape to character codes included in any remaining two groups of the first to the third groups, respectively, and a character code that is a test object and the other character codes are distinguishable on the display of the output information using the fonts.