diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cafa2de..cb64cdc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -47,9 +47,13 @@ jobs:
         run: julia -e 'using Pkg; Pkg.develop(PackageSpec(path=".")); Pkg.add(PackageSpec(url="https://github.com/timholy/Revise.jl")); Pkg.test("Revise")'
       - name: Test while running Revise
         if: ${{ matrix.os == 'ubuntu-latest' && matrix.version != '1.0' }}
-        run: julia --project -e 'using Pkg;
-                                 Pkg.add("Revise");
-                                 Pkg.test("CodeTracking"; coverage=true, test_args=["revise"])'
+        run: TERM="xterm" julia --project -i --code-coverage -e 'using InteractiveUtils, REPL, Revise, Pkg;
+                                                                 Pkg.add("ColorTypes");
+                                                                 @async(Base.run_main_repl(true, true, false, true, false));
+                                                                 sleep(2);
+                                                                 cd("test");
+                                                                 include("runtests.jl");
+                                                                 REPL.eval_user_input(:(exit()), Base.active_repl_backend)'
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v1
         with:
diff --git a/Project.toml b/Project.toml
index db182a8..3517470 100644
--- a/Project.toml
+++ b/Project.toml
@@ -13,8 +13,9 @@ julia = "1"
 [extras]
 ColorTypes = "3da002f7-5984-5a60-b8a6-cbb66c0b333f"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+REPL = "3fa0cd96-eef1-5676-8a61-b3b8758bbffb"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["ColorTypes", "LinearAlgebra", "SparseArrays", "Test"]
+test = ["ColorTypes", "LinearAlgebra", "REPL", "SparseArrays", "Test"]
diff --git a/README.md b/README.md
index 16f56c1..8711314 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,8 @@
 # CodeTracking
 
+[![Build status](https://github.com/timholy/CodeTracking.jl/actions/workflows/ci.yml/badge.svg)](https://github.com/timholy/CodeTracking.jl/actions/workflows/ci.yml)
+[![Coverage](https://codecov.io/gh/timholy/CodeTracking.jl/branch/master/graph/badge.svg?token=bBzCYyj19O)](https://codecov.io/gh/timholy/CodeTracking.jl)
+
 CodeTracking can be thought of as an extension of Julia's
 [InteractiveUtils library](https://docs.julialang.org/en/latest/stdlib/InteractiveUtils/).
 It provides an interface for obtaining:
diff --git a/src/CodeTracking.jl b/src/CodeTracking.jl
index c561667..d1a6f42 100644
--- a/src/CodeTracking.jl
+++ b/src/CodeTracking.jl
@@ -1,3 +1,13 @@
+"""
+CodeTracking can be thought of as an extension of InteractiveUtils, and pairs well with Revise.jl.
+
+- `code_string`, `@code_string`: fetch the source code (as a string) for a method definition
+- `code_expr`, `@code_expr`: fetch the expression for a method definition
+- `definition`: a lower-level variant of the above
+- `pkgfiles`: return information about the source files that define a package
+- `whereis`: Return location information about methods (with Revise, it updates as you edit files)
+- `signatures_at`: return the signatures of all methods whose definition spans the specified location
+"""
 module CodeTracking
 
 using Base: PkgId
@@ -159,7 +169,7 @@ function signatures_at(filename::AbstractString, line::Integer)
             end
         end
     end
-    error("$filename not found in internal data, perhaps the package is not loaded (or not loaded with `includet`)")
+    throw(ArgumentError("$filename not found in internal data, perhaps the package is not loaded (or not loaded with `includet`)"))
 end
 
 """
diff --git a/src/utils.jl b/src/utils.jl
index 8a8a367..9dad520 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -1,3 +1,5 @@
+# This should stay as the first method because it's used in a test
+# (or change the test)
 function checkname(fdef::Expr, name)
     fproto = fdef.args[1]
     fdef.head === :where && return checkname(fproto, name)
diff --git a/test/runtests.jl b/test/runtests.jl
index fbe1fe1..ee5756d 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1,7 +1,7 @@
 # Note: some of CodeTracking's functionality can only be tested by Revise
 
 using CodeTracking
-using Test, InteractiveUtils, LinearAlgebra, SparseArrays
+using Test, InteractiveUtils, REPL, LinearAlgebra, SparseArrays
 # Note: ColorTypes needs to be installed, but note the intentional absence of `using ColorTypes`
 
 using CodeTracking: line_is_decl
@@ -67,6 +67,10 @@ isdefined(Main, :Revise) ? Main.Revise.includet("script.jl") : include("script.j
     show(io, info)
     str = String(take!(io))
     @test startswith(str, "PkgFiles(CodeTracking [da1fd8a2-8d9e-5ec2-8556-3022fb5608a2]):\n  basedir:")
+    ioctx = IOContext(io, :compact=>true)
+    show(ioctx, info)
+    str = String(take!(io))
+    @test match(r"PkgFiles\(CodeTracking, .*CodeTracking(\.jl)?, String\[\]\)", str) !== nothing
 
     @test pkgfiles("ColorTypes") === nothing
     @test_throws ErrorException pkgfiles("NotAPkg")
@@ -86,17 +90,6 @@ isdefined(Main, :Revise) ? Main.Revise.includet("script.jl") : include("script.j
     oldlookup = CodeTracking.method_lookup_callback[]
     CodeTracking.method_lookup_callback[] = m -> error("oops")
     @test whereis(m) == ("REPL[1]", 1)
-    # Test with definition(String, m)
-    if isdefined(Base, :active_repl)
-        hp = Base.active_repl.interface.modes[1].hist
-        fstr = "__fREPL__(x::Int16) = 0"
-        histidx = length(hp.history) + 1 - hp.start_idx
-        ex = Base.parse_input_line(fstr; filename="REPL[$histidx]")
-        f = Core.eval(Main, ex)
-        push!(hp.history, fstr)
-        @test definition(String, first(methods(f))) == (fstr, 1)
-        pop!(hp.history)
-    end
     CodeTracking.method_lookup_callback[] = oldlookup
 
     m = first(methods(Test.eval))
@@ -109,6 +102,10 @@ isdefined(Main, :Revise) ? Main.Revise.includet("script.jl") : include("script.j
     end
     m = first(methods(f150))
     src = Base.uncompressed_ast(m)
+    idx = findfirst(lin -> String(lin.file) == @__FILE__, src.linetable)
+    lin = src.linetable[idx]
+    file, line = whereis(lin, m)
+    @test endswith(file, String(lin.file))
     idx = findfirst(lin -> String(lin.file) != @__FILE__, src.linetable)
     lin = src.linetable[idx]
     file, line = whereis(lin, m)
@@ -167,6 +164,35 @@ end
 
         # issue #23
         @test !isempty(signatures_at("script.jl", 9))
+
+        @test_throws ArgumentError signatures_at("nofile.jl", 1)
+
+        if isdefined(Revise, :add_revise_deps)
+            Revise.add_revise_deps()
+            sigs = signatures_at(CodeTracking, "src/utils.jl", 5)
+            @test length(sigs) == 1       # only isn't available on julia 1.0
+            @test first(sigs) == Tuple{typeof(CodeTracking.checkname), Expr, Any}
+            @test pkgfiles(CodeTracking).id == Base.PkgId(CodeTracking)
+        end
+
+        # REPL (test copied from Revise)
+        if isdefined(Base, :active_repl)
+            hp = Base.active_repl.interface.modes[1].hist
+            fstr = "__fREPL__(x::Int16) = 0"
+            histidx = length(hp.history) + 1 - hp.start_idx
+            ex = Base.parse_input_line(fstr; filename="REPL[$histidx]")
+            f = Core.eval(Main, ex)
+            if ex.head === :toplevel
+                ex = ex.args[end]
+            end
+            push!(hp.history, fstr)
+            m = first(methods(f))
+            @test definition(String, first(methods(f))) == (fstr, 1)
+            @test !isempty(signatures_at(String(m.file), m.line))
+            pop!(hp.history)
+        elseif haskey(ENV, "CI")
+            error("CI Revise tests must be run with -i")
+        end
     end
 end