On-the-fly Suggestions of Rewriting Method Deprecations

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:: Deprecate w ActiveSupport : : Deprecation

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-FBSOJOHGSPN0UIFS-BOHVBHFT class Legacy def old_method(arg) # do old thing
end def new_method(arg) # do new thing end end w .BJOUBJOTLegacyDMBTT w "EETnew_method w %FQSFDBUFTold_method -JCSBSZ"VUIPS -FUTTBZBMJCSBSZBVUIPS

-FBSOJOHGSPN0UIFS-BOHVBHFT -JCSBSZ"VUIPS $VSSFOUBQQSPBDIFT Gem :: Deprecate class Legacy #
@deprecated Use {#new_method} def old_method(arg) warn "Use #new_method instead" # do old thing end def new_method(arg) # do new thing end end class Legacy def old_method(arg) # do old thing end def new_method(arg) # do new thing end extend Gem : : Deprecate deprewrite :old_method, :new_method, 2025, 4 end :"3% warn

class Legacy def old_method(arg) # do old thing end def
new_method(arg) # do new thing end extend Deprewriter deprewrite :old_method, to: "new_method( {{ arguments } } )" end -FBSOJOHGSPN0UIFS-BOHVBHFT w %FDMBSFUBSHFUUPSFXSJUF w %FDMBSFUSBOTGPSNBUJPOSVMF -JCSBSZ"VUIPS 6TF%FQSFXSJUFS 💡

--- ./script.rb +++ ./script.rb @@ -37,6 +37,6 @@ legecy =
Legacy.new -legecy.old_method(arg) +legecy.new_method(arg) -FBSOJOHGSPN0UIFS-BOHVBHFT legacy = Legacy.new legacy.old_method(arg) -JCSBSZ6TFS 3VOVTFSDPEF UIFOHFU fi YFTPSTVHHFTUJPOT MPHHJOH EJ ff fi MFT BQQMZJNNFEJBUFMZ %FQSFXSJUFSJEFOUJ fi FTDPEFUPCFSFXSJUUFOBUSVOUJNFBOESFXSJUFT PSPVUQVUTTVHHFTUJPOTUPSFXSJUF

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%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT # @param method_name [Symbol] The name of the
method to deprecate # @param from [String, nil] Pattern to match for transformation # @param to [String] Pattern to transform to def deprewrite: (Symbol method_name, to: String, ?from: String?) -> void Deprewriter.deprewriteTJHOBUVSF deprewrite :old_method, from: ".call_node[name=old_method]", to: "new_method( {{ arguments } } )" &YBNQMF fromJTBOPQUJPOBMBSHVNFOUUPTUSJDUMZ fi MUFSBDBMMOPEF )PXUPXSJUFUSBOTGPSNBUJPOSVMFT 1

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%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT NodeMutation :: PrismAdapterFYBNQMF adapter = NodeMutation :: PrismAdapter.new
replacement = "new_method( {{ arguments.arguments.0 }} :, {{ arguments.arguments.1 }} :)" original_code = "old_method(arg1, arg2)" call_node = Prism.parse(original_code).value.statements.body.first new_code = adapter.rewritten_source(call_node, replacement) # => "new_method(arg1:, arg2:)" )PXUPXSJUFUSBOTGPSNBUJPOSVMFT 1

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT NodeMutation :: PrismAdapterFYBNQMF adapter = NodeMutation :: PrismAdapter.new
replacement = "new_method( {{ arguments.arguments.0 }} :, {{ arguments.arguments.1 }} :)" original_code = "old_method(arg1, arg2)" call_node = Prism.parse(original_code).value.statements.body.first new_code = adapter.rewritten_source(call_node, replacement) # => "new_method(arg1:, arg2:)" $PEFUSBOTGPSNBUJPOJTQPTTJCMFJGXFQBTTBO"45OPEF )PXUPXSJUFUSBOTGPSNBUJPOSVMFT 1

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%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT class Legacy def old_method(arg) # do old thing
end def new_method(arg) # do new thing end extend Deprewriter deprewrite :old_method, to: "new_method( {{ arguments }} )" end 8IBUIBQQFOTPOVTJOHdeprewrite )PXUPUSBOTGPSNDPEF 2

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT def deprewrite(method_name, to:, from: nil) class_eval do old
= "_deprecated_ #{ method_name}" alias_method old, method_name define_method method_name do |*args, &block| # Transformation logic here send old, *args, &block end end end .FUIPEDBMMJOUFSDFQUJPO w 4BNFUFDIOJRVFBT Gem :: Deprecate. deprecate w 1SFTFSWFPSJHJOBM NFUIPECFIBWJPSUP SFTVNFMBUFS IUUQTEPDTSVCZMBOHPSHFONBTUFS(FN%FQSFDBUFIUNM )PXUPUSBOTGPSNDPEF 2

def deprewrite(method_name, to:, from: nil) class_eval do old = "_deprecated_
#{ method_name}" alias_method old, method_name define_method method_name do |*args, &block| filepath, line = Gem.location_of_caller source = File.read(filepath) # Transformation logic here send old, *args, &block end end end %FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT (FU fi MFQBUIBOESFBEUIF fi MFUPEFUFDUBDBMMTJUF )PXUPUSBOTGPSNDPEF 2

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:: Visitor def initialize(method_name, line, from: nil) # Set instance variables end # @param source [String] source code to search def find(source) parsed_result = Prism.parse(source) parsed_result.value.statements.accept(self) @node # @return [Prism :: CallNode] end def visit_call_node(node) # Find call node here end end )PXUPUSBOTGPSNDPEF 2

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT Prism :: CallNode IUUQTEPDTSVCZMBOHPSHFONBTUFS1SJTN$BMM/PEFIUNM legacy = Legacy.new result
= legacy.old_method(1, 2) do |a| # block arg end do_something(with: result) DBMMOPEFPG #old_method )PXUPUSBOTGPSNDPEF 2

class CallSiteFinder < Prism :: Visitor def initialize(method_name, line, from:
nil) @node_query = from ? NodeQuery.new(from, adapter: :prism) : nil end def visit_call_node(node) if @node_query matched = @node_query.query_nodes(node) @node = matched.first if matched.any? else @node = node end end end %FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT IUUQTHJUIVCDPNTZOWFSUIROPEFRVFSZSVCZ 6UJMJ[FOPEFRVFSZSVCZUPTUSJDUMZ fi OEDBMMOPEF deprewrite :old_method, from: ".call_node[name=old_method]", to: "new_method( {{ arguments }} )" %FUFDUJOHNFUIPEDBMMTJUFT )PXUPUSBOTGPSNDPEF 2

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT $PEFUSBOTGPSNBUJPO class Transformer def initialize(source, node, transform_with) #
Set instance variables end def transform # @return [String] return @source if @node.nil? before_node = @source[0 . .. @node.location.start_offset] new_code = transform_call_node after_node = @source[@node.location.end_offset .. ] before_node + new_code + after_node end end )PXUPUSBOTGPSNDPEF 2

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT $PEFUSBOTGPSNBUJPO class Transformer def initialize(source, node, transform_ #
Set instance variables end def transform return @source if @node.nil? before_node = @source[0 .. . @node.locat new_code = transform_call_node after_node = @source[@node.location.e .. before_node + new_code + after_node end end legacy = Legacy.new result = legacy.old_method(1, 2) do |a| # block arg end do_something(with: result) *UUSBOTGPSNTPOMZDBMMOPEF BOEQSFTFSWFTTVSSPVOEJOHDPEFDPOUFYU )PXUPUSBOTGPSNDPEF 2

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT $PEFUSBOTGPSNBUJPO IUUQTHJUIVCDPNTZOWFSUIROPEFNVUBUJPOSVCZ class Transformer def transform_call_node adapter =
NodeMutation :: PrismAdapter.new receiver_code = @node.receiver ? " #{ @node.receiver.slice}." : "" call_node = Prism.parse(@node.slice.gsub(receiver_code, "")). value.statements.body.first receiver_code + adapter.rewritten_source(call_node, @transform_with) end end 6UJMJ[FOPEFNVUBUJPOSVCZUPUSBOTGPSNDBMMOPEF deprewrite :old_method, from: ".call_node[name=old_method]", to: "new_method( {{ arguments }} )" 4FUBT@transform_with )PXUPUSBOTGPSNDPEF 2

%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT $PEFUSBOTGPSNBUJPO legacy = Legacy.new result = legacy.old_method(1, 2)
do |a| # block arg end do_something(with: result) legacy = Legacy.new result = legacy.new_method(1, 2) do |a| # block arg end do_something(with: result) 5IJT NFUIPESFOBNJOH JTUIFTJNQMFTUEFQSFDBUJPOQBUUFSO )PXUPUSBOTGPSNDPEF 2

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--- ./script.rb +++ ./script.rb @@ -37,6 +37,6 @@ legecy =
Legacy.new -legecy.old_method +legecy.new_method %FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT 1SPWJEFNPEFTUPIBOEMFSFXSJUUFODPEF -PH.PEF 4IPXXBSOJOHTXJUI TVHHFTUFEDIBOHFT %J ff .PEF (FOFSBUFQBUDI fi MFTUPCF BQQMJFE 3FXSJUF.PEF "VUPNBUJDBMMZVQEBUF TPVSDF fi MFT *TSFXSJUJOHDPEFBUSVOUJNFTBGF 3

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%FQSFXSJUFS3VCZ*NQMFNFOUBUJPO%FUBJMT )PXUPHFOFSBUFEJ ff GPSMPHEJ ff NPEFT class Deprewriter ::
Diff def to_s original_diff = Diffy :: Diff.new( @source, @rewritten_source, include_diff_info: true, diff: "-u").to_s formatted_timestamp = @timestamp.strftime("%Y-%m-%d %H:%M:%S.%N %z") header = [ " - -- #{ @filepath}\t #{ formatted_timestamp}", " + ++ #{ @filepath}\t #{ formatted_timestamp}" ].join("\n") [header, original_diff.lines[2 .. ].join].join("\n") end end IUUQTHJUIVCDPNTBNHEJ ff Z --- ./script.rb +++ ./script.rb @@ -37,6 +37,6 @@ legecy = Legacy.new -legecy.old_method +legecy.new_method (FOFSBUFEJ ff *TSFXSJUJOHDPEFBUSVOUJNFTBGF 3

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Legacy def old_method(arg) # do old thing end def new_method(arg) # do new thing end end require "deprewriter" class Legacy extend Deprewriter deprewrite :old_method, to: "new_method( {{ arguments } } )" end 8JMMUIF3VCZFDPTZTUFNBEPQUJU 4

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On-the- fl y Suggestions of  Rewriting Method Deprecations Masato Ohba
(@ohbarye)

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On-the-fly Suggestions of Rewriting Method Depr...

On-the-fly Suggestions of Rewriting Method Deprecations

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